Bala Shark: The Definitive Care Guide 2020 (Diet, Setup, & Tankmates)

The Bala shark is known by many names. Balanitiocheilus melanopterus is also known as the silver shark, the shark minnow, or the tricolor shark. But don’t let the name “shark” fool you – these guys aren’t voracious or vicious and they won’t decimate your community tank.

Before adding these fish to your aquarium, there are some things you should know about the care of the Bala shark.

Bala Shark Care Guide

Species summary

The name comes from their body shape and larger-than-expected adult size. They have a rigid, triangular dorsal fin that stands upright and sport a torpedo-like body shape that is reminiscent of the sharks you might typically think of. They typically will reach a length of 10 to 13 inches in captivity, and have a life expectancy of approximately 10 years when properly cared for.

These fish come from Southeast Asia, originally able to be found in medium and larger rivers and lakes. They thrived, at one time, in Thailand, Sumatra, Borneo, and the Malayan peninsula, but have become rare in many of the areas they once inhabited. In fact, they’re believed to be extinct in some regions that they once thrived in.

It’s not clear why the Bala shark has become more scarce in the wild, whether it’s due to overfishing, pollution, or river damming. But, despite its status on the IUCN Red List of Threatened Species since 1996, these fish are wildly abundant and quite common in the common aquarium.

Typical Behavior

The Bala shark is anything but shark-like.

They’re shoaling fish by nature, so it’s advisable to keep six of these fish together for comfort and perceived security. They’re relatively timid and are frightened easily, especially when they’re the newest additions to a tank.

They’re very active fish even when they’re feeling a bit shy, though, so you will get to enjoy watching them explore their new home and any tank mates that they might have. Although, they do have times of inactivity or when they feel stressed, where they will hide in plants and roots around your tank. This is normal behavior though, especially in a new environment.

The Bala shark is a peaceful fish that shouldn’t cause any disruptions in your aquarium. They can have an appetite though and may knock smaller fish away from food unintentionally. They may also eat smaller fish as they get bigger, so keep that in mind if and when you decide to bring these fish home.

They’re also known to occasionally jump, so you’ll want to keep a snug lid or hood on your tank.

Bala Shark Appearance & Size

As previously touched on, the Bala shark isn’t a true shark at all, but it does have a similar enough appearance to one to warrant the name. With its upright, rigid, triangular dorsal fin and its torpedo-shaped body, it cuts a silhouette that reminds most people of a great white shark.

Bala sharks have a shiny, metallic body with well-defined scales. They have large, noticeable eyes and a heavily-forked teal that is tinted slightly in a yellow color. They also have signature blat tips along their dorsal caudal, pelvic, and anal fins.

Another thing you should note about the Bala shark is that it grows to a decent size. They are typically sold in pet shops at lengths ranging from two to four inches, but when fully grown they average about a foot in length, usually falling somewhere between 10 and 13 inches.

Compatible Tank Mates

Bala sharks, when kept in groups of at least four and ideally six, are peaceful fish that can be kept with other, similarly-sized peaceful or mildly-aggressive fish. As long as the tank mates of choice don’t attack or unnecessarily harass your Bala sharks, they should be fine.

Additional tankmates may include fish such as:

  • Other Bala sharks
  • Other large cyprinids
  • Rainbowfish
  • Corydoras
  • Certain species of gourami
  • Rasbora
  • Char
  • Minor tetra
  • Tetra

Be sure not to add any carnivorous fish to your tank, such as cichlids, as they may harass your Bala shark with its flashy appearance.

You should also avoid breeding fish in a tank where Bala sharks are being kept, as they’re highly likely to eat the fry. They may also try to eat smaller fish such as neon tetras.

Avoid keeping shrimp in the same tank as your Bala sharks, as they’re highly likely to be aggressive toward smaller shrimp species and will try to eat them if given the chance.

Sex Differences

Under regular circumstances, there are no visible differences between the male and female Bala shark except that the male is often longer than the female. Additionally, during the spawning season, your female Bala sharks may appear to be a bit rounder or stockier than the males.

Keeping Multiple Bala Sharks

As previously stated, Bala sharks are shoaling fish and do best when kept in a group of at least four. Ideally, you will keep six of these fish together in the aquarium and will be able to adequately accommodate them as they grow.

Keeping these fish as individuals not only increases the likelihood of stress-related illness or death but also increases the chances of your Bala shark becoming aggressive toward other tank inhabitants. This can be dangerous especially as your Bala shark grows.

Tank Setup

When you choose to get a Bala shark, or more preferably multiple Bala sharks, you should first be sure that you have the proper equipment ready to take care of them. It’s also best to make sure that their new home is already up and running for a bit before bringing them home and introducing them to the new tank.

What Size Aquarium do They Need?

The aquarium tank that you use for your Bala sharks should be long and large since they’re such active swimmers they’ll be able to have and use the space at their leisure. To begin with, you’ll need at least a 45-gallon tank, and you will have to steadily increase the tank size as they grow.

By the time they are adults, they will ideally be living in a tank that is spacious enough that each fish essentially has 45 gallons of space to themselves at any given time. At a minimum, for four Bala sharks, you want to have them housed in a large 150-gallon tank that is at least five feet long.

Water conditions

Bala sharks, while relatively hardy, can be particularly sensitive to changes in their water parameters. This is another strong argument to keep their water clean and balanced for proper health and longevity.


Bala sharks enjoy and thrive in water that is kept around 77 degrees Fahrenheit. You can let the temperature vary up to two degrees higher or lower without any problems, but try to keep to that range and don’t allow the temperature of the water to change suddenly or drastically.

PH Balance

They prefer a pH balance between the range of 6.5 and 8. This is a wider range than some other fish have, and may allow you to really diversify the kinds of fish that cohabitate with your Bala sharks.

Water Hardness

The one parameter that Bala sharks are not overly-sensitive to is the hardness of their water. They do have a preference, and that preferred range of hardness is between 10 and 13 dGH, but they can still thrive without the water meeting this requirement. This is more of a suggested parameter than a necessity.


The Bala shark does not require any special or additional lighting. They do well with moderate-strength lights on a regular day and night cycle. Using a timer can help to keep your fish well-regulated and will also help the growth of any plants in your aquarium.

Decor and Substrate

Bala sharks do not really care one way or the other about decor in the tank. This is because they will, mostly, be swimming in the mid-range area of the water and prefer open spaces where they can move freely and without the worry of colliding with other objects.

If you would like to use plants and driftwood or other items in your tank, try to place them along the inner edges of the perimeter so that they do not inhibit the swimming paths of your fish. Smooth rocks are also attractive decor items that the fish may interact with in some capacity.

Floating plants may help to deter the Bala sharks in your aquarium from jumping out, but you should still use a fitted lid or hood for optimum security. They will accept any substrate type, but tend to prefer darker colors as it makes them feel more secure in their environment.

How to Care for Bala Sharks

Since Bala sharks have their natural habitat in the freshwater rivers and lakes of Southeast Asia, they have a high preference and need for clean, fast-flowing waters. Since they spend most of their time actively swimming around, they tend to hang out in the clear middle range of the water.

Because Bala sharks are sensitive to the conditions of their water, you will want to carry out regularly-scheduled partial water changes every week. Let them settle into their tank for up to a month after introducing them without disturbing them, and then each week you can begin partial water changes of up to 25 percent of the tank’s volume. Working slowly and methodically will help keep your sharks from feeling stress or anxious.

Use a powerful external filter that can keep up with the waste that your Bala sharks produce, and preferably one that also allows for adequate water flow and circulation is preferred. Also, remember that Bala sharks sometimes like to jump out of their tanks, so keep a secure lid or hood on the tank at all times.

Food and Feeding

The natural diet of the Bala shark includes insects, crustaceans, plant parts, algae, and larvae. This is an ideal and varied diet for them in the wild. However, in captivity, Bala sharks are typically not picky eaters, and they will eat any type of food offered to them, alive or dead.

You can and should make sure to diversify their diet and food types with things like bloodworms, different types of plankton, and food items like diced fruits or vegetables, particularly spinach. However, the core part of the Bala shark’s diet should be comprised of high-quality dry food such as a high-quality flake or pellet.

As they grow and, in fact, due to their larger sizes as adults, they need a healthy amount of protein fortifying their diet. You can give them additional protein by offering shrimp and other protein-rich foods, whether live or frozen, such as Daphnia,bloodworms, shrimp,  and mosquito larvae.

In the most ideal circumstances, the Bala shark will eat two to three times a day. Use small portions that they can eat completely within a two to two-and-a-half-minute period to minimize food waste and waste build-up in your tank.

When fed correctly and appropriately, they are strong and healthy and will require no additional supplementation to their diet.

Poor or low-quality food and a lack of varied diet for your Bala shark may result in problems with their digestive system. It can also result, ultimately, in a shortened lifespan or increase in the likelihood of them developing an illness or disease.


Breeding Bala sharks is not typically a tricky process, but you will want to keep the size of your fish in mind when doing so.

To breed your Bala sharks, you’ll want to separate them from the main tank at about four months old and keep them in their own space. Prepare a tank of at least 65 gallons ahead of time for this purpose and make sure that the temperature of the water always reads at about 77 degrees Fahrenheit.

If you choose to place plants or decorations in the tank, make sure that they’re out of the main swimming area of your fish. You can leave the bottom of the tank entirely clear as well if you choose, as this will help when it’s time to look for fry and will also make it easier to clean the tank. Alternatively, you can place a spawning or breeding net at the bottom to make the breeding process easier.

You can stimulate the spawning process of your Bala sharks by slowly and gradually increasing the water temperature up to about 82 degrees Fahrenheit. Remember that any quick or sudden changes to the pH or temperature of the water can harm not only the breeding process but the fish themselves.

Spawning will take place in the morning under normal circumstances and will last for a few hours, after which the male Bala sharks will fertilize the spawned eggs with milt. It’s important, at this stage, to make sure that you have strong circulation in the tank to help effectively distribute the milt.

After the eggs are fertilized, you’ll want to remove your external filter from the spawning tank and replace it with an internal filter and sponge to prevent injury to your fry. You’ll also want to remove the parents for similar reasons.

Larvae will begin to appear within 24 hours, and after about three to four days they will become fry. Feed the fry ciliates for those first few days and after four or five days, begin giving them nauplii of Artemis or cyclops.

Your Bala shark fry may grow at different speeds. This is perfectly normal, however, it will require you to closely monitor them and remove larger ones from the spawning tank as necessary to a different tank separate from the parents and smaller siblings.

Bala Shark Diseases

Bala sharks are not particularly more vulnerable to any singular disease than other fish in your tank might be. They can become infected with common fish diseases and ailments such as ich and dropsy, as well as aquatic parasites.

Ich is a fairly common skin infection in fish. It causes small white spots to appear on the fish’s scales and will make your fish scratch themselves on rocks, gravel, decor, and anything else they can find with a rough enough surface.

Dropsy will cause your fish to swell with a build-up of fluid. Usually, this is a symptom of a much more serious problem, such as a parasitic or bacterial infection.

You can use regularly-suggested treatments to medicate and cure your fish of these types of ailments. Be sure to closely monitor your fish while you’re administering treatment, and keep an eye out for any additional or unusual signs in behavior, activity, appetite, and appearance.

Even once all signs of infection are gone, you should continue medicating your fish for a few days to be absolutely certain that the problem is completely resolved. Make sure to read any instructions or warnings on the bottle or container to avoid underdosing or overdosing your fish.


The Bala shark makes a stunning, lively addition to most aquariums. It has a simple elegance and charm to it with its shiny, metallic scales and distinctive black tips.

But, because they grow to such a significant size and are highly active, they do require a lot of space. Make sure that you can provide them with the space, food variety, and water quality that they need to thrive and live their best life.

If you can do those things, these fish are relatively easy to take care of and will make a great addition to your community tank.

Richard Rowlands
Richard Rowlands

Hello fellow aquatics enthusiasts! My name is Richard Rowlands. I’m an aquarium keeper and enthusiast and have been for about 25 years or so. While I won’t claim to be the end-all expert on aquatic life, I will say that I know my way around a tank.

Pictus Catfish: The Complete Care, Species, & Breeding Guide

Pictus Catfish Care Guide

If you’ve always wanted to care for a fish and have perhaps graduated from the easiest fish to care for (the guppy) and would like something just a shade more exotic, then you might want to look at the pictus catfish. Much more docile than their mammalian counterparts yet named for the interesting ‘whiskers’ surrounding their face, catfish are beautiful specimens which would add immense grace to your at-home aquarium.

Let’s discuss the ways we can best care for pictus catfish.

Species Profile

Often deemed ‘unmistakeable’, the pictus catfish does have a striking appearance which makes it much sought-after in the world of amateur fish procurers. It has an energetic personality, which means that it won’t ‘just float there’, but instead that as its owner you’re in for hours of delight as you watch the fish gambol about its tank.

The coloring of the catfish is beautiful as well! Known as both the Pictus Catfish and the Angel Catfish, this fish hails from South America, where it was first found by Franz Steindachner an Austrian zoologist in the late nineteenth century.

Pictus Catfish Habitat

As they first came from South America and they are quite active, we can make a few inferences based on its initial habitat as to how to customize its tank. Since they like to swim fast, catfish usually do best in larger tanks—around one hundred gallons or so. Keeping them in a smaller tank would stress them out unnecessarily.

The South American reference comes in with their requiring warmer temperatures for their water. You may have to employ a water heater and a few satellite thermometers as well as routine checks to ensure that the tank is kept up to livable standards for your catfish!



Catfish are easy to tell apart from other fish. They’re named for the long tendrils or ‘whiskers’ that come from the front of their face, much like a cat’s whiskers; but their coloring and patterning is also extremely identifiable. They have white bodies with black spots—to continue with the feline connections, they are much like a fish version of snow leopards.

The catfish have a white barbell—something akin to an exterior spine—which goes all the way down the side of the fish, almost from its head, down to its caudal fin. That’s another easily identifiable characteristic of a catfish.

Its whiskers are similar to the antennae of an insect or the tongue of a dog; they use them for sensory proprioception. For example, when the water around them gets muddy, catfish are able to use their whiskers to help them navigate anyway.

Telling the difference between male and female catfish can be tricky, as they are virtually identical. However, when the female catfish reaches an age of sexual maturity, they will tend to be just a little bit larger and rounder than their male counterparts—possibly so that they’re ready to carry their prospective young.

Tank Conditions

As they hail from South America, a pictus catfish’s tank should be warm and bright during the day (and dark at night). Since catfish are usually found swimming through sandy riverbeds, adding sand to the bottom of their tank will also help them feel at home. Remember to get them a tank that’s large enough for zipping around in!

Because they’re river fish, you should also try to simulate the current of a river in their tank. (This is another reason that a very large tank is crucial!) To do this, you will have to invest in a high-quality filter—however, this will be one of the largest investments you will make. After that, fish are relatively low maintenance.

Luckily, a heavy-duty filter will serve at least one other purpose when you have pictus catfishes on hand! Catfish are notoriously good at producing large amounts of waste. Because their waste is inherently toxic to them, you’ll have to help filter it out — which, for these fish, is something you’ll be doing anyway.

As far as tank accessories go, because these catfish are from the South American forest rivers, they’re used to lots of driftwood and tree trunks to swim around and hide behind. Giving them moss, rocks, and driftwood in their tanks will go a long way towards making them feel at home.

Lastly, the catfish is mostly a nocturnal fish. If you want to see them active during the day, when we humans are awake, you’ll want to keep the tank very dimly lit or underlit—this will help them feel safe coming out when you can see them.

As far as specific water conditions go, you’ll want to keep the temperature relatively warm (between 75-81 degrees Fahrenheit) and the pH between 7.0 and 7.5.


In the wild, pictus catfishes are omnivores and scavengers. Whatever they can find to eat, they will. In domesticity, this is convenient but also a major responsibility on your part. They’ll eat anything you put in the aquarium—which makes giving them the food they need quite easy, but also raises the danger of them eating something that they shouldn’t if you aren’t diligent about keeping strange objects out of the tank.

As far as what you should be concentrating on feeding them, remember that the catfish likes to spend a lot of time circling the bottom of their tank. Therefore, the usual lighter-than-air flakes won’t do very well for them—they won’t notice they’re there! Fish food distributors have solved this problem by manufacturing sinking pellets specifically for catfish. Pick up a quantity of good quality sinking pellets for your catfish, and you can’t go wrong.

You can also change it up every now and again by giving them some brine shrimp or beef heart, which they’ll nibble on to their heart’s content for hours; or frozen worms, or any of an array of vegetables. Anything they don’t touch should  be removed from the tank to reduce chance of bad bacteria growth.

Another good asset of them being scavengers is that they will eat any naturally growing algae that grows out of your substrate. You don’t have to worry about cleaning this out at all!

Because catfish are very active, they do have very large appetites. If your brand of fish food has a range of appropriate amounts of food to give to catfish, it’s better to err on the larger side of the spectrum—otherwise the catfish’s natural high activity levels will turn into high levels of aggression.

The flip side of this large amount of food is that your catfish will be naturally producing high levels of waste. As mentioned above, investing in a high-quality water filter will go a long way towards helping take care of this, but you should also test the water periodically to make sure that its levels are in a good place, and prioritize switching out 25% of the water on a weekly basis.

Pictus Catfish Tankmates and Compatibility

A good rule of thumb is that a 150 gallon tank can support up to 4 catfish. This might seem like a lot—it is!—but remember that catfish are very active and beautiful; your return on investment will be high.

Pictus catfish aren’t known for being incompatible with other fish—in fact, they’re quite friendly, and they love having other fish to swim around with. There are significant caveats or warnings, however, that go along with this observation.

  1. Firstly, pictus catfish require large amounts of food, and they will become aggressive if they go hungry. If you aren’t giving them the food that they need and you do populate their tank with smaller fish, they will assume that the smaller fish are food and kill and eat them.
  2. Pictus catfish are fast! One of their favorite activities is zooming around their tanks at high speed—part of the reason that they’re such big eaters. It’s not a good idea, therefore, to include several larger or slower fish in the cage along with the pictus catfish, as the catfish might harm the larger and slower fish with their sharp fins as they swim around.
  3. As a general rule of thumb, you should make sure that if you’re including any breeds of fish that aren’t catfish in your tank with the catfish, the catfish should be the smallest fish in the tank. As noted elsewhere, catfish aren’t necessarily carnivorous, and are quite peaceful. However, if you lapse your feeding schedule, any smaller fish will be the first to feel the repercussions of your negligence.

Because of these stipulations, many people wonder if it’s worth keeping several different breeds together. Of course it is! Living in the wild, pictus catfishes would naturally be associating with many different types of fish. However, in domesticity, you might not want to deal with the fallout of the food chain. Know that depending on what you want to have in your home, having a mixed array of fish, only catfish, or even just one singular catfish, are all completely fine options—catfish can live separately or together.


Because the pictus catfish is a popular freshwater fish, they are very difficult to breed in the environment of a home aquarium. One of the biggest reasons this is the case is that catfish need lots of room in order to reach sexual maturity; they just aren’t able to grow to the size they need to be in order to reproduce when they’re at all cramped. And their definition of ‘cramped’ is very different from what others perhaps may be.

If you’re looking to breed catfish, the long and short of it is that you’ll need a very large tank of about 200 gallons in your home. This might be difficult! However, it’ll be necessary if you’re looking to have your catfish reproduce.

However, know that even if you invest in the right size of tank, the chances are still very low that you’re going to be able to observe breeding. Very few people who have catfish at home have been able to observe even the signs of breeding maturity, let alone the process of actually breeding.

However, we do know that in the wild, it’s a process wherein the female catfish lays eggs, and then the male catfish comes along to fertilize them.

If you’re serious about trying your hand at breeding catfish in domesticity, ultimately, know that your chances are very low, and it starts with having a gigantic amount of room in your home for a good sized tank. Then, it would be a good idea to get in contact with a community of fish breeders and others who like to prioritize the quality of their fish meetups—perhaps even professional breeders, too; that way you can get a good idea of what you need to do to succeed for your fish.

Pictus Catfish Diseases

An interesting fact is that catfish don’t have scales. Unfortunately, this makes it much easier for them to contract various diseases, so you definitely need to make sure that you keep the water in the specific windows for pH and temperature mentioned above. However, if you prioritize keeping the water in the right window for their overall health, pictus catfishes usually don’t contract any kind of regular diseases. They’re very easy to keep healthy and safe once you get into a routine.

The Challenges of Keeping Pictus Catfish in Your Aquarium?

One easily identifiable challenge of keeping a pictus catfish in your aquarium is simply the fact that the catfish’s fins get extremely sharp—much like the claws of a cat. While this will certainly impact how you carry the fish—in a plastic box, not in a net or bag—it might also impact any non-catfish tank mates or other aquarium accessories that you leave in with your fish. The other difficulty, assuming you aren’t trying to breed, is simply that they are omnivorous, and that you must feed them regularly. If you don’t, they will become aggressive and eat anything in sight.

Richard Rowlands
Richard Rowlands

Hello fellow aquatics enthusiasts! My name is Richard Rowlands. I’m an aquarium keeper and enthusiast and have been for about 25 years or so. While I won’t claim to be the end-all expert on aquatic life, I will say that I know my way around a tank.

The Complete Iridescent Shark Care Guide (2020): Care, Size & Tank Mates

Iridescent Shark

Species Profile Overview

Iridescent sharks (previously Pangasius hypophthalmus, currently Pangasianodon hypophthalmus) are a species of large, freshwater catfish. Which probably seems strange if you only know them as iridescent sharks. In fact, they are also commonly known as Sutchi catfish, Pangasius catfish, and striped catfish.

Iridescent sharks aren’t actually a shark species at all, and they originate from Asia. These fish can grow to be between 3.3 and 4.3 feet in length. They can live for approximately twenty years if given the proper space and a relatively stress-free environment.

Creating such an environment for these fish can be difficult, especially for those new to the hobby of keeping an aquarium. For this reason, they’re not strictly advised for people to keep at home, though an advanced keeper with a large aquarium or outdoor enclosure may be able to successfully keep these fish.

The iridescent shark can be kept relatively happily in a 60-gallon aquarium, but since they prefer to school, you will likely need an aquarium or aquatic space that is at least 40 feet in length, or 300 gallons or more.

Typical Behavior

Iridescent sharks can easily be scared, even as large adults. They’re very skittish and timid, and any movement outside of their environment or space can cause them to make a wild, blind dash to get away from the perceived threat. This can, understandably, be dangerous to them as well as to their tank mates, especially in an aquarium.

This skittishness can cause your iridescent shark to thrash and hit their head or fins on decor in the aquarium or on the glass of the tank itself. It may not be intentionally destructive while trying to escape what it sees as a threat, because these fish have very poor eyesight overall.

If other fish are caught up in the iridescent shark’s attempts to evade danger, they can be hurt as well. It’s important that your iridescent shark feels safe and comfortable at all times as a result.

They like to school as juveniles for safety purposes and may continue to do so as adults, but primarily they should be kept in a school of five or more as juveniles because more aggressive fish may pick on them by biting at their fins.

To alleviate any stress caused by more aggressive species, you should only keep iridescent sharks with large, peaceful fish. There should be a noted emphasis on the fact that these peaceful tank mates need to be large – any fish that the iridescent shark can fit into its mouth as it grows, it will try to consume.

While they are timid and may even play dead if they feel truly threatened, these are very active fish. In their natural habitat, they live in large rivers that have sandy or rocky beds. In these rivers, the iridescent shark tends to stay in the mid-range water layers.

To satiate their need for space and activity, you will want a tank or enclosure that’s on the larger end of the spectrum. If you have difficulty making a large space feel secure for these fish, adding a variety of plants can help.

Also keep in mind that these fish are known jumpers, so it will be necessary to use a tight-fitting panel lid or hood to keep them safe and in the water.

They tend to be more active during the day than other catfish.

Iridescent sharks Appearance

It may be clear by the name, but the iridescent shark is, in fact, iridescent. What this means is that when it moves, the scales can sometimes reflect light in different colors or may simply appear particularly shiny.

This shiny appearance usually fades with age, as do the black strips on and below their lateral lines. The lateral line should be pointed out because it is actually a sensory organ. It’s full of nervous tissue that is used to help the fish detect changes in the water, and may help them identify potential threats.

By the time they are adults, iridescent sharks are actually a fairly uniform gray color. They’re sold as juveniles in part to their more attractive appearance and partially because they become such large fish as adults.

They range from 3.3 to 4.3 feet in length as adults, with the females typically being plumper and larger than the males.

A unique quality of these sharks when compared to other catfish species is that they don’t have the bonier body armor of some other species. These bony plates usually help catfish to protect themselves while still allowing for a relatively free range of motion, but they’re absent in the iridescent shark.

The iridescent shark does have long, whisker-like barbels. The barbels help them to feel out their environment and search for food. This is useful because sometimes these fish are located in low-visibility, low-light, and high-sediment areas, on top of them already not having the best eyesight.

Food and Feeding

Iridescent sharks are omnivorous. This means, in the simplest of terms, that they thrive on a diet of both animal- and plant-based food items. They will take any offered food item under the most favorable circumstances. These fish will feed on everything from algae to other, smaller fish.

As juveniles, you can supplement the diet of the iridescent shark in several ways with a varied diet. With naturally-blooming algae or algae wafers, seed plants, zooplankton, small insects, and tropical flake or pellet foods your juvenile iridescent shark should be healthy and have a well-rounded diet. As they age and become adults, they will also accept small fish, certain fruits, and crustaceans as well.

Additionally, they will also take frozen food items such as bloodworms and brine shrimp. Feed these items every two or three days to keep your fish interested in different foods, as it will keep them healthy and active.

Many keepers will feed these fish a higher-protein diet as juveniles and move on to a more plant-based diet for the adults, as the iridescent shark may begin to lose their teeth the older they get. Be sure to keep this in mind and feed appropriately.

If you choose to offer your iridescent sharks live feeders, such as comet goldfish, minnows, or guppies, be sure that you buy them from a local pet store and quarantine them in a separate tank for three to five days. This will ensure that they are healthy and won’t pass on any illnesses, parasites, or other ailments to your sharks.

Tank Setup

When you choose to get an iridescent shark, or more appropriately a school of them, you need to know first that you have the appropriate set-up for them.

Tank Size

A singular iridescent shark can live comfortably with tankmates in an aquarium that is at least 40 gallons. However, it’s advised to give these fish much more space to roam and be active. This is especially true if you have a school of four to five iridescent sharks, which will need an aquarium of at least 100 gallons as juveniles and at least a tank size of 300 gallons as adults. Add approximately 150 gallons worth of space for each additional iridescent shark.

Since they come from wide, large rivers in the wild, you want to simulate that environment’s space to the best of your ability. Provide an open swimming space, especially along the middle layers of the space, and add driftwood and rocks to the bottom of your tank where the substrate is.

Additionally, since they are skittish particularly as juveniles, you may want to add some plants. Specifically, floating plants are a great option for reducing stress in these fish and gives them a sense of safety. They also prefer softer substrates, such as mud or sand.

Water Parameters

As is the case with most fish, iridescent sharks do not tend to respond well to frequent changes in their water quality or the parameters of their tank. While they are hardy, they are not invincible and are very vulnerable to high levels of stress. So to ensure a high quality of life for your fish, you need to make sure that you can maintain the correct parameters for their needs.

The pH should be between 6.5 and 7.5 in the aquarium. Anything in that range is safe, but once your fish have become accustomed to a particular pH balance, try not to let it fluctuate too much.

You should keep the temperature of the water somewhere between 72 and 79 degrees Fahrenheit. If possible, you can gradually adjust the temperature of the water to mimic seasonal changes, but don’t venture beyond these parameters as it will upset your fish. Put the heaters in places where the fish cannot accidentally break them if they get scared or skittish – undergravel heaters or external in-line heaters work well.

The water hardness may be something that you do not typically think of as a factor for your fish unless you keep particularly sensitive species, but the iridescent shark does have a preference. They prefer water within the range of 2 to 20 dGH. The GH is the measurement of the level of magnesium and calcium that is dissolved in the water.  


Iridescent sharks prefer a moderate amount of light. This is usually fine for some fast-growing plants that may give the sharks an additional sense of security, such as hornwort or anacharis. These plants should grow fast enough that even if your fish are nibbling on them, it shouldn’t be noticeable.

Water Flow and Filtration

You will need a powerful filtration system in place while keeping this kind of fish, as they produce a significant amount of organic waste. External filters are preferred for these fish and their tank mates because they typically also provide the level of water flow that the iridescent shark prefers.

If your external water filter is not creating a moderate level of water movement or flow, you may need to add an additional air pump to generate the appropriate amount of circulation that your fish need and enjoy.  

As previously mentioned, iridescent sharks are particularly messy by nature. But to keep them both happy and healthy, their water needs to be clean and manageable. This can be difficult, so you’ll want a powerful external filtration system to handle most of the work for you.

You also want to make sure that you do weekly water changes.

About 25 to 30 percent of the aquarium water will need to be changed each week, and since iridescent sharks require a large tank to thrive in, this can be a time-consuming activity. This is especially true since you want to change the water slowly to avoid scaring your fish unnecessarily.

Iridescent Sharks Tank Mates

As previously stated, aggressive tank mates should be avoided particularly while your iridescent sharks are in their juvenile and adolescent stages. The tank mates of your iridescent sharks should be large, peaceful fish that can also be schooling fish if you’d like. You want to look for species of fish that are large enough or will be large enough that they won’t be eaten by your iridescent sharks.

There are many large peaceful or semi-aggressive, but not overtly so, fish that will make good companions and tank mates for your iridescent sharks. These include:

  • Kissing gourami
  • Silver dollars
  • Plecostomus
  • Salvin’s cichlids
  • Some other large catfish species
  • Fire eels
  • Bichir
  • Texas cichlids

The iridescent shark can live with any non-aggressive or semi-aggressive fish of a similar size and which will not harass the shark itself. It should not be housed with fish with a low activity level, as it may agitate those fish.

Iridescent sharks should also not be housed with crabs, shrimps, or snails. As soon as they can, they will begin to eat these tank inhabitants, so unless you’re maintaining a population in a separate tank and feeding off the excess crustaceans to your iridescent sharks, it’s not advised to keep them with these fish.


To date, there have been no successful breedings of iridescent sharks in captive aquarium environments. This is because of the spawning habits of the fish and the sheer size of the adults. This fish is migratory and will travel upstream from its normal habitat to spawn in the late spring and summer months.

This behavior coupled with the size of the fish makes it nearly impossible to duplicate amicable breeding conditions in captivity. It should also be noted that, while there is sexual dimorphism in the adults of this species, it’s much more difficult to distinguish the differences at a juvenile age. Since this is the age most pet stores will sell these fish at, you’re not guaranteed the sex of the fish you will receive.

Iridescent sharks are bred and produced in huge ponds in Southeast Asia, in places like Singapore and Thailand. They may also be harvested from wild populations and then raised in large, floating containers.


Iridescent sharks, like most fish, are susceptible to several common diseases, including fungal diseases. As a scaleless catfish, if they happen to contract ich, they can be difficult to treat without prior experience. Most ich cures will advise you to use a half-strength dose to treat your catfish, which may prolong exposure and infection risk to other fish in the tank.

An easier solution is to use treatments such as Pimafix or Melafix to treat your infected tank, depending on appropriateness, if iridescent sharks are in the tank. Use these medications as directed, and if you are uncertain, do not hesitate to contact the manufacturer or company behind the medicine to ask them any questions or concerns that you may have.

Since iridescent sharks are easily frightened, they’re liable to scratch themselves trying to escape things that they believe to be threats. And since they’re a scaleless species, it’s important to be ready to treat them for any injuries they cause to themselves. For this, you’ll want to use some slime coat replacement such as Stress Coat or NovAqua.

Be sure that you avoid using medications for these fish that are based on copper or potassium permanganate. These chemicals can be dangerous for your iridescent shark. You can, however, use malachite green or formalin, just make sure you use either a quarter or a half of the recommended dosage.

Remember that all medications for your fish should be used with caution. Double-check with a veterinarian familiar with aquatic animals or with the manufacturer of the medication for any safety questions or concerns.

Are Iridescent Sharks Suitable For Your Aquarium? (Summary)

In conclusion, iridescent sharks can be a rewarding species to keep so long as you keep them happy, healthy, and stress-free. But, they are also difficult to keep, and the space they require alone for long-term keeping rules them out as good fish for most hobbyists. Additionally, even when you can afford the space and maintenance that they require, they have a lifespan of twenty years, so you have to plan for long-term care of these large fish.

Richard Rowlands
Richard Rowlands

Hello fellow aquatics enthusiasts! My name is Richard Rowlands. I’m an aquarium keeper and enthusiast and have been for about 25 years or so. While I won’t claim to be the end-all expert on aquatic life, I will say that I know my way around a tank.

Bristlenose Pleco: Tank Setup, Care Guide, Breeding And More…

Bristlenose Pleco Care

The world of fishkeeping and collecting some of the most unique and interesting fish available has become an emerging hobby for millions.

Many various species of Ancistrus have taken the center stage within the hobby, with the Bristlenose Pleco being a popular choice for fish keepers.

They’re closely related to the pleco stomas. In laymen terms, they’re close with catfish.

They look similar and are bottom feeders, much like their catfish cousins.

They’re a wonderful addition to any tank and are easily affordable. If you’re an amateur fish keeper and are looking for a unique species to add to your tank, the Bristlenose Pleco is an excellent option.

Species Summary

If you’re looking for an affordable, unique tank-cleaner, the Bristlenose Pleco delivers.

Beyond being a smart addition to any take, they’re also great company. They play well with other fish and only grow to a size of approximately five inches at most.

The Bristlenose Pleco hails from the waters of South America, typically in rivers and streams. More specifically, they’re native to the Amazon.

This makes them preferential to aerated water, similar to the flowing currents found in their native habitat.

Like other catfish, the Bristlenose is also a bottom feeder. They’ll slide along the bottom of your tank and feed off bits of plants and other plant material.

They’re known to be a great beginning species for a fishkeeper and are easily found throughout the United States. Their initial cost is relatively low as well. You’ll find them averaging around the $5 mark.

Bristlenose Pleco Appearance

Most of the time when people think of catfish, the mind travels to 75-pound monsters pulled from the depths of the Missouri or Mississippi Rivers.

Thankfully, the Bristlnose Pleco is a much friendlier looking companion for your fish and household.

They typically grow to approximately three to five inches and may have a variety of markings associated with them. You’ll find them with spots that are colored brown, white, yellow, green, or gray. They’re a little bit like skittles!

All Plecos come equipped with a bony plating. You’ll see that their mouths have an underbite, similar to other catfish species. Their body is also flat and wide. It’s a unique look, catfish or otherwise.

The structure and shape of the Bristlenose Pleco’s head are where the species’ name originates from. Both males and females have tentacles that may look flesh-like that protrude from the front of the head or the snout. They look incredibly ‘bristly.’

The coloring may be uneven throughout their coat. Some spots and splotches may be darker or lighter and can look drastically different from each other.

Their undersides are typically a lighter color but could be dark as well. However, it should be lighter than the rest of their body. In contrast, the backsides are typically a darker color.

In some ways, the Bristlenose Pleco is a cute-looking fish. Their heads are larger than the rest of their bodies and they have large eyes. When looking at one, they may appear to be ‘innocent’ and even adorable. Since they play well with others, and their species, you could have multiple of these beautiful fish in your tank.

If you’re lucky enough to find one, albino Bristlenoses also exist. All the colors and markings go out the window in this case and you’ll have to look at the distinct features of the fish to identify it.

Males will typically be larger, especially if they’re an older generation. This will also be reflected in their bristles and whiskers. Additionally, a male’s tentacles will be located on their heads. In general, males will be much larger than the females.

Females will, of course, be smaller in general. However, the key difference will be found in the bristles. Their bristles will be extended from the snout rather than the head.

Typical Behavior

The Bristlenose Pleco is a playful, hardy fish that can be suitable for almost any tank conditions.

They’ll get along with other species and because they’re so durable and resilient, you’ll find than they can adapt to most tank settings with the right setup.

However, it should be noted that male Bristlenoses will become territorial during the breeding process. The males will defend their nest fiercely and will defend it from other fish if he perceives it as a threat.

This is mostly a non-issue but it is important to keep in mind if you’re considering breeding Bristlenose Plecos.

Beyond the male’s territorial behavior when breeding, the Bristlenose Pleco won’t cause you any issues in terms of behavioral issues.

Tank Setup

Finding the right setup for your Bristlenose Plecos isn’t difficult but is the most important step in providing the best home possible to them.

Because they’re a smaller species that also can withstand a large variety of water conditions, your tank options will be fairly open.

Tank Size

You’ll want a 40-gallon tank at a minimum, although a 20-gallon will satisfy the species in a pinch or emergency. They produce an excessive amount of waste so you’ll find that your tank will quickly get dirty if it is too small.

A larger tank will help manage their waste better and avoid disturbing any other tankmates your Bristlenose may have. As always, it’s a good idea to invest in high-quality filters to provide the best habitat for all the species in the tank.

Water Parameters

They can also handle a large range of pH levels. From acidic to alkaline, the Bristlenose Pleco will adapt well. Although, younger Bristlenoses are more sensitive to pH levels when compared to their adult counterparts. You should keep in mind that a young Bristlenose may need to have the pH levels adjusted to better suit them.

If you’re new to the world of fishkeeping, obtaining an adult Bristlenose may be an easier option for you. The adults become much hardier and you won’t have to adjust pH levels nearly as much, if at all.

Ensure your tank is well aerated as the Britslenose will prefer waters that are similar to their native habitats of rivers and streams. The aerated water will imitate similar conditions of flowing water and increased oxygen levels.

A good option for ensuring that your tank imitates the flowing, oxygenated waters of South America is to implement an under-gravel water system. This system will provide oxygen that shoots out from the bottom of the tank, similar to the current of a stream or river.

This imitation will not only help your Bristlnose feel at home, but it will provide a highly-oxygenated environment for all the species in your tank. This is never a bad thing and will help keep all the fish in your tank healthier than ever.

Similarly, their native habitat provides many shaded areas for them to hide and relax in. This is why you’ll want at least one cave, if not a few more to recreate that environment. Beyond caves, driftwood and large, canvasing plants can be good options to provide more shade as well.

Because the Bristlenose Pleco is a bottom feeder, you’ll want to have many additional structures and features that line the bottom of your tank.

Here are some ideas for the structure to put on the bottom of your tank:

  • Driftwood
  • Caves of various sizes
  • Lively plants and plant-like material
  • Roots
  • Gravel

Tank Mates That Pair Well With the Bristlenose Pleco

The Bristlenose Pleco is a friendly fish who loves other friendly fish. They’re sociable and are there to have a good time, you won’t find any anger issues in this fish.

The Bristlenose Pleco is so friendly that some fishkeepers will pair them with aggressive fish that don’t traditionally get tank mates. It’s been known that Bristlenose Plecos can sometimes live with African cichlids or bettas.

This is because the Bristlenose Pleco is locked and loaded when it comes to defense. Their bone-plated armor, robust endurance, and bristles all work together to keep themselves safe. However, these mechanisms are made for defensive purposes. Your Bristlenose won’t be using them as weapons to assault other fish.

While it is a possible option, you should always remember to take the best care of your fish and not expose them to environments that could potentially be harmful to them.

Tanks with a large community of fish will find these to be a welcomed addition. Here are some species that would pair well with the Bristlenose Pleco:

  • Guppies
  • Tetras
  • Platies
  • Other easy-to-care-for, friendly fish

The Bristlenose Pleco is truly a marvelous addition to a friendly, community tank and should be one of the first fish to consider investing in for the beginning fish keeper.

When and What to Feed Bristlenose Plecos

One of the great benefits of the Bristlenose Pleco is its ability to feed with little effort on your end. Driftwood and gravel will be excellent places for algae to consistently grow and feed your Bristlenose.

The natural growing algae alone should be sufficient food for the Bristlenose and it’ll save you from having to clean your tank more frequently. Although some fishkeepers recommend adding tablets to supplement the rest of their diet.

If you feel like your tank doesn’t produce enough vegetation for the Bristlenose to feed on, or if you want to ensure your fish is getting the absolute best feeding, tablets and other vegetation are good options.

Tablets are made from several different manufacturers and are designed to supplement the diet of bottom-feeding fish. These tablets will provide extra nutrients and protein to round out their food pyramid.

If tablets aren’t your style, you could provide your Bristlenose with a variety of vegetation. Try cabbage leaves, pea, carrots, and other similar vegetables that degrade relatively quickly. All of these vegetables will provide plenty of fiber and other nutrients to keep your Bristlenose healthy and happy.

While it may seem tempting to solely rely on vegetables and other produce, remember that Bristlenose Plecos do best when you’re imitating their natural habitat. While it may be easier to throw a few veggies in the tank a couple of times a day, you should always look to provide natural algae for feeding through structure and surfaces in the tank. This is, by far, the best way to feed your Bristlenose Pleco.

At most, feed your Bristlenose twice a day. Although, if you have a supply of algae in your tank, you can skip a feeding or even a full day if need be. The algae will keep your fish fine for at least a few days, especially if your tank is known to produce a large number of algae

It should be noted that while the Bristlenose Pleco is a herbivore, their bottom-feeding habits will sway them from feeding on your plants. Unless severely underfed, the Bristlenose won’t be knocking over your plants and feasting on their stems. If you do notice that your Bristlenose is starting to feed on the plants and other lively vegetation in your tank, it is a sign that something is wrong with them.

This typically will mean that your Bristlenose isn’t being fed enough. However, it could be more serious. Call a professional if you feel like your Bristlenose is acting out of the ordinary for specific advice.

A good way to tell if your Bristlenose is being fed right is through their coloration. Their coloration should be strong and healthy-looking. If you notice their color begins to fade and they look generally unwell, it can be a sign that their food is inadequate.

Like other catfish, the Bristlenose Pleco will generally feed at night. They’re considered nocturnal and will do most of their feeding when you’re not around. If you catch one in the act of feeding, take notice and watch it! You may not get the opportunity again for a while.


Breeding the Bristlenose Pleco is relatively easy if you’ve been paying attention.

To trigger a spawn, the Bristlenose must feel comfortable and be healthy. This means keeping on top of your feeding, providing a large enough tank size, providing adequate water, and quality structure.

The larger the tank, the better; at least in breeding scenarios. Ideally, a tank around 55 to 60 gallons will be perfect for breeding. This size of the tank should have two breeding areas located at opposite ends of the tank.

If you simply don’t have a tank that large, don’t’ fret. It’s possible to breed the Bristlenose Pleco in a tank as small as 25 to 30 gallons.

These breeding areas should have many features, specifically driftwood and caves. The males will want to breed in a cave or protected area. This spot must be designed to make the Bristlenose feel comfortable and safe within it. After all, they’ll be vehemently protecting it for the duration of the spawn.

On that note, it should be reaffirmed that the Bristlenose male will become territorial when breeding. If other fishes come near their breeding area or pose a threat to the nest, a male Bristlenose may strike out in defense of their territory.

The quality of water should be at the top of your list for things to improve if you’re wanting to breed Bristlenose Plecos. Like other catfish, they require high-quality water as well as a current to initiate a spawn.

This is why a good aeration system is key when attempting to breed the Bristlenose. Do your best to imitate moving water throughout the tank to increase the chances of a successful spawn being initiated.

If you’ve taken care of these two things as well as provided a high quality of life for your Bristlenose, it should have little problems beginning to breed. Like other fish in its family, they will start breeding almost immediately if conditions are to their liking.

Their breeding is known to easily get out of control if conditions are optimal. As soon as one spawn has left the nest, a male will often time have another batch on the way.

This is usually the largest thing to look out for when breeding Bristlenose Plecos.

Honestly, it’s not a bad problem to have!

In Summary

If you’re looking for the perfect beginner species for your tank, the Bristlenose Pleco is an excellent pick.

You’ll find that these hardy fish can handle most mistakes you may make when beginning your fish keeping journey and they’ll be easily maintained. On top of being a beautiful companion to your tank, they also make your life easier by cleaning the tank for you. That’s a win-win in everyone’s life.

The only downside to this fish is their territorial issues when breeding (which can happen quite a lot) and their lifespan. The Bristlenose Pleco will live an average of five or more years. While this is a long time when compared to stereotypical fish in a tank, it’s not nearly as long as other members of its family.

These pretty little fish are easy to grow attached to, so don’t be heartbroken when it’s over sooner rather than later.

Richard Rowlands
Richard Rowlands

Hello fellow aquatics enthusiasts! My name is Richard Rowlands. I’m an aquarium keeper and enthusiast and have been for about 25 years or so. While I won’t claim to be the end-all expert on aquatic life, I will say that I know my way around a tank.