A 20 gallons fish tank is perfect for those who want to add a little bit of life to their home without going overboard. They’re big enough to house a nice stock of fish, some plants, and a variety of other aquatic creatures but small enough to fit on most shelves and stand without taking up too much space.
These mid-sized aquariums are most often recommended for those who want to get into fishkeeping. Contrary to small fish tanks – anything smaller than 20 gallons, these have a sufficient water volume that provides a more stable environment, making them more forgiving of beginner mistakes.
Additionally, these tanks are not so large that require much maintenance, setup, and care. This is important because many new fishkeepers often get discouraged when they realize how much work is needed to maintain a large aquarium.
Of course, the fish you intend to stock in your 20-gallon fish tank will play a big role in deciding on the rest of the equipment and plants you’ll need. But don’t worry; we’re here to help you figure it all out!
20 Gallon Fish Tank Basics
Let’s start with the basics of a 20-gallon fish tank.
|Tank Size||L x W x H||Empty Weight||Filled Weight|
|20-gallon (high)||24″ x 12″ x 16″||25 lbs.||225 lbs.|
|20-gallon (long)||30″ x 12″ x 12″||25 lbs.||225 lbs.|
The dimensions are important to take into consideration when stocking your fish tank. Not only does it affect the number of fish you can have, but the type of fish as well.
Although personal preference comes into play, a longer tank is often better than a taller one because it provides more surface area and offers more decoration options.
Another thing to consider is the weight of the tank. A full 20-gallon fish tank can be heavy, so make sure it’s placed on a sturdy surface that can support the weight.
Now that we’ve gone over the basics of a 20-gallon fish tank let’s talk about stocking.
How to Choose A Centerpiece Fish to Stock
Before you head to your local fish store or order anything online, you need to ask yourself a few fundamental questions. These will help determine which centerpiece show fish is best for your 20-gallon tank.
- How big is the fish going to get?
- Is the fish territorial and aggressive?
- Is it a fin nipper?
- Does it eat live plants?
- Does it dig in the substrate?
- What are the required water parameters? (pH, hardness, temperature, etc.)
- Is it a gregarious or solitary fish?
- Is it wild-caught or captive-bred?
- How much does it cost to buy?
Top 5 Centerpiece Fish for 20 Gallon tank
While there are many different centerpiece fish for a 20 gallons tank, we’ve put together a list of our favorites. These fish are not only beautiful but also relatively easy to care for, perfect for those just starting out.
#1 Dwarf Gouramis (Trichogaster Lalius)
Dwarf Gourami is one of the most sought-after fishes for freshwater aquariums. Not only are they attractive, but they’re also relatively easy to care for.
Scientifically known as the Trichogaster Lalius, these freshwater fish are a part of the gourami family and can only grow to be about 3.5″ (8.8 cm) long.
They have an elongated body and have been line-bred to produce a variety of color morphs.
There are several most popular variations below.
- Powder Blue Dwarf Gourami
- Neon Blue Dwarf Gourami
- Blue Dwarf Gourami
- Flame Dwarf Gourami
- The Honey Dwarf
Dwarf Gouramis are native to South Asia and can be found in the slow-moving, thickly vegetated rivers and streams of India, Pakistan, and Bangladesh.
Gourami is labyrinth fish, meaning they have a unique organ that allows them to breathe air directly from the surface. That’s why you’ll likely find them spending a good amount of time at the top or middle of your aquarium.
|Scientific Name:||Trichogaster Lalius|
|Common Name:||Dwarf Gouramis|
|IUCN Red List:||LC|
|Max Size:||3.5″ (8.8 cm)|
|Temperature:||72 – 82°F (22 – 27°C)|
|PH:||6 to 7.5|
|Water hardness:||10–20 dH|
#2 Bolivian Ram (Mikrogeophagus altispinosus)
For those looking for a centerpiece South American Cichlid that is both stunning and relatively easy to care for, the Bolivian Ram is a great option.
Bolivian ram cichlids are endemic to the tributaries of the Amazon River Basin in Bolivia and Brazil, where they inhabit freshwater streams and lakes with sandy or muddy substrates.
These eye-catching fish have many common names in the trade, such as the Bolivian ram cichlid, Bolivian Butterfly, ruby crown cichlid, and Bolivian Ram.
Bolivian Rams have an elongated oval-shaped body, the main coloration is tan or silver, and their extended and showy rayed fins are decorated with bright red edging. Sometimes, faint dark bars can be seen running across their body. Males often have long filaments on their fins.
Fully grown, Bolivian rams will reach a length of 3.1 inches (8cm); males grow larger than females but usually don’t reach 3.5 inches at all.
Bolivian Rams are peaceful cichlids. In a 20 gallons tank, you can keep a single fish with other small schooling fish and bottom-dwellers that share similar water parameters in a community South American cichlid setup or a pair in a planted tank.
|Scientific Name:||Mikrogeophagus altispinosa|
|Common Name:||Bolivian Butterfly, Ruby Cichlid, Ruby Clown Cichlid|
|Origin:||Bolivia, Brazil, South America|
|Size:||3.1 inches (8cm)|
|KH:||0 – 10 dKH|
#3 Ram Cichlid (Mikrogeophagus ramirezi)
If you can’t find Bolivian Rams in your LFS, another great centerpiece fish for a 20 gallons freshwater aquarium is its cousin, Ram Cichlid (Mikrogeophagus ramirezi), which is more widely available.
M. ramirezi has been introduced to the aquarium trade for years under many trade names, including Ram, blue ram, dwarf butterfly cichlid, butterfly cichlid, German blue ram, and Ramirez.
In the wild, this small freshwater fish is endemic to the Orinoco River basin and lives in slow-flowing streams and flooded forest areas with heavy aquatic plants.
Wild-caught specimens are more colorful than tank-bred ones. They have a beautiful gold or silver body with numerous black markings. Red or orange is usually found on the tips of the fins.
As their name suggests, its body is usually accompanied by a contrasting reflective electric blue stripe, giving the fish a flashy and attractive appearance.
Ram cichlids are small, laterally compressed freshwater fish that grow about 2 to 3 inches long. Due to its small adult size and relatively peaceful nature, it’s not recommended to be kept with these aggressive cichlid species.
In the wild, they are found in large groups, so it’s best to keep them in pairs with other small and peaceful fish in your 20-gallon aquarium.
|Scientific Name:||Mikrogeophagus ramirezi|
|Common Name:||Ram, blue ram, dwarf butterfly cichlid, butterfly cichlid, German blue ram, and Ramirez|
|Origin:||Orinoco River basin, South America|
|Size:||2 to 3 inches|
|pH:||5.0 to 7.0|
|Temperature:||74 to 82F (23 to 28C)|
|KH:||0 – 10 dKH|
|Lifespan:||2 to 3 years|
#4 Apistogramma Dwarf Cichlids (Apistogramma sp.)
Any small-sized Cichlids list would not be complete without at least one of the Apistogramma Dwarf Cichlids.
Apistogramma is a large genus of cichlids found in South America, with more than 93 species described to date. They’re found in the western Amazon Basin and Orinoco Basin, where they inhabit clear, black and white shallower water.
These popular aquarium fish are well known for their bright colors and varied personalities. Unfortunately, some Apistos are not for newbies since they are very sensitive to water quality conditions. As a potential owner, you must be devoted to providing the best care for your fish.
Apistos can grow to be 0.8 to 3 inches long, depending on the species. They are typically brightly colored, with males often being more colorful than females.
The most popular beginner-friendly Apistos for a 20 gallons aquarium are A. cacatuoides (Cockatoo cichlid) and Apistogramma borellii (Umbrella Cichlid). These two species are relatively peaceful and adaptable.
|Scientific Name:||Apistogramma sp.|
|Common Name:||Apistogramma Dwarf Cichlids|
|Size:||0.8 to 3 inches|
|Care:||Beginner to Advanced|
|pH:||5.0 to 7.0|
|Temperature:||6.0 to 7.0|
|KH:||2 – 15 dKH|
|Lifespan:||5 to 8 years|
#5 Kribs (Pelvicachromis pulcher)
Now we have the famous South American Dwarf Cichlids, but it’s not the only dwarf cichlid out there; The West African Dwarf Cichlids, Kribensis (Pelvicachromis pulcher), are well known by cichlid keepers.
Being some of the first West African cichlids to be introduced into the aquarium trade, they have been captive-bred for many generations and now come in various colors and patterns. The most common color morphs are yellow and red, in addition to the line-bred albino variety.
Kribs are small cichlids that males can grow to be about 4 inches long while females stay a bit smaller at about 2.5 inches. They are found in blackwater streams with acidic and soft water conditions in the wild.
Given their small size and peaceful temperament, they make great tank mates for other small community fish such as danios, cory cats, plecos, and barbs. However, these fish tend to be fin nippers, so you should not keep them with Angels unless you have a larger tank.
In a 20-gallon aquarium, a breeding pair of Kribs would be a good centerpiece fish. If you want to keep more than a pair, then you should consider getting a larger tank.
|Scientific Name:||Pelvicachromis pulcher|
|Common Name:||Krib, Common Krib, red Krib, super-red Krib and rainbow Krib, purple cichlid|
|KH:||0 – 12 dKH|
Are They the Fish for You?
So there you have it, the five best centerpiece fish for your 20-gallon tank! With such a wide variety of colors and personalities, there’s sure to be a perfect fit for every aquarium owner.
Do you have a favorite centerpiece fish? Let us know in the comments below!