Common Pleco Size in the Aquarium & Wild (Ideal Common Pleco Tank Size)

Common Pleco tank Size is supported by our readers. When you buy through links on our site, we may earn a commission.

The Common Pleco (Hypostomus plecostomus) is one of the most sought-after ornamental freshwater fish in the aquarium trade. These bottom-dwelling scavengers are known for their large size, hardiness, and fairly easy to care for.

But even though these fish are low-maintenance, there are many things potential owners should know before they purchase one, including Common Pleco size and the minimum tank size for the Common Pleco.

This guide goes over these two questions in detail so that you can make an informed decision about whether or not a Common Pleco is the right fish for your aquarium.

Without further ado, let’s get started.

Common Pleco Size in the wild & Aquarium

How Big will a Common Pleco get? In the aquarium, the typical Common Pleco size is 12 – 15 inches in length for a full-grown fish, and some specimens can reach up to a maximum size of 20 inches (50 cm). They can get even bigger in the wild, the largest on the record being 30 inches (76 cm).

These fish are sold by the thousands at a size of 2-3 inches (5.0-7.6 cm) when they’re young, and they fast grow species. Due to their large full-grown size and rapid growth rate, these fish are not ideal pleco species for many hobbyists.

How Fast Does a Common Pleco Grow?

It’s QUITE common for them to add 3-5 inches during their first year of life. After that, their growth rate starts to taper off until they reach their full size. It takes about 2-3 years for a Common Pleco to grow to its full size, depending on your purchase size, a mix of good care and luck.

Below are many common pleco sizes by age records from hobbyists around the world:

AgeSizeTank size
2 Months2.5 inches75 gallons
6 Months8 inches75 gallons
1.5 years7.5 inches90 gallons
3 – 4 years12 inches75 gallons
 4-5 years16 inches75 gallons
2 years10 inches55 gallons
9 months8 inches 30 gallons

What is the Minimum Tank Size for Common Pleco?

As we mentioned earlier, common pleco can grow to be quite large, so they need a spacious tank to accommodate their size.

For a single adult Common Pleco, we recommend tank size no smaller than 75 gallons (48″ x 18″ x 21″), a 125 gallons (72″ x 18″ x 21″) is optimal. If you plan on keeping a group of juveniles at the common purchase size, a 30-gallon tank can do the job. 

How to Choose the Right Common Pleco Tank Size? 

Common Pleco size

Although we have provided the minimum tank size recommendations, we understand that the number is not for everyone.

When it comes to choosing an aquarium tank for your Common Pleco, here are a few things to consider before you make your purchase:


As any experienced aquarium owner knows, the footprint of a fish tank is just as important as the volume. Adult Common Plecos are often very territorial, and a larger tank with big footprints will give them more space to claim as their own. 

Because of their potential size, any footprint/dimensions smaller than 48″ (L) x 18″ (W) might stunt their growth. Of course, this assumes that you have a healthy fish and provide optimal care.

Additionally, you can keep more fish in an aquarium with a large footprint. 

Water Volume

It’s a widely accepted rule of thumb in the fishkeeping world that the larger the volume of water in your tank, the more stable the environment will be. 

One common problem with small tanks is that the ammonia and nitrate levels can change quickly and become toxic to your fish. This is especially true in a tank with a high stocking density. Moreover, Common Plecos can produce a lot of waste, which can further impact the water quality fast.

In a larger tank, on the other hand, these levels will change more slowly, giving you more time to take corrective action.

The Number of Fish

One of the most important factors for Common Plecos care is how many you want to keep together. Adult Common Plecos can become quite territorial, and they might not do well with other fish of the same species.

Of course, this all changes when they’re juveniles. Juveniles can be kept together in a group until they start to show aggression towards each other.

For those planning to add Common Pleco to a community tank, we would recommend at least a 125-gallon tank. If you just keep one common pleco alone in a tank, well, it’s rare to see, but a 75-gallon tank is a minimum size we would recommend. 

Keeping two Common Plecos together is definitely not recommended unless you have a 250 gallons tank or large. 

Growth Rate

Not all fish grow at the same rate; Common Plecos are no different. The growth rate of your common pleco will largely depend on the genes and the quality of care it receives. 

If you are lucky enough to have a common pleco with great genes, it might outgrow most of its tank mates and need to be moved to a larger aquarium. On the other hand, if you have a common pleco that only grows a few inches in the first year, it might not reach its full-size potential.

How To Grow Common Plecos Fast?

There is no holy grail method when it comes to helping your Common Plecos reach their potential size. Instead, old-fashioned tricks like getting larger tanks and feeding them nutritious meals are key factors in success!

Get A Bigger Tank

We have said it before, and we will say it again: a larger tank is always better.

A common pleco that has plenty of space to grow will always outgrow one that doesn’t. If you are serious about helping your fish reach their potential, upgrading to a larger tank should be one of your top priorities.

A large footprint tank not only gives your fish more space to grow but also lets you create a more natural-looking aquascape with plenty of rocks, plants, and driftwood.

Feed Them Right

What your fish eat plays a big role in how fast they grow. Just like humans, fish need certain nutrients to reach their full growth potential.

Being one of the best algae eaters, Common Plecos are not fussy eaters and will accept most food items. A good diet for common plecos should include both plant matter and meaty foods. You can supply them with vegetables like zucchini, cucumber, peas, and squash. 

For protein foods, live or frozen foods like bloodworms, brine shrimp, and blackworms are all great choices.

You should also supplement their diet with algae wafers and driftwood for a source of fiber. Driftwood is especially important for common plecos since it helps them with their digestion. 

Common Plecos spend most of their time at the bottom of the tank and prefer to stay hidden among the rocks and wood. So when you are feeding them, make sure that the food sinks to the bottom where they can easily find it.

Maintain Water Quality

In my humble opinion, this is the most crucial factor in any aquarium, not just Common Pleco tanks.

No matter how big or how well-equipped your tank is, it will never be successful if you don’t maintain good water quality.

Water quality not only plays a role in the health of your fish but also in their growth rate. Fish that are living in clean and well-oxygenated water will always grow faster than those that don’t.

To maintain good water quality, you need to do regular water changes and make sure your filtration system is up to par. You should also check your water parameters regularly and take corrective action if necessary.

Here are some basic water parameters you should stick to:

  • Water temperature: 70°F to 81°F
  • pH level: 6.5 to 8.0
  • Water hardness: 5 to 25 dGH
  • Ammonia: 0 PPM
  • Nitrite: 0 PPM 
  • Nitrate: Below 20 PPM


Now that you know all about the Common Pleco size, we hope this article has been helpful in your quest to create the perfect home for your fishy friend! Remember, the key to success is starting with a large tank and providing them with a nutritious diet. With a little bit of care, your common pleco will reach its full growth potential in no time!

If you have any tips or suggestions on helping common plecos grow, we would love to hear from you in the comments below!

Was this article helpful?
Jeff Colt

Jeff Colt

Hello, I'm Jeff- an aquarium enthusiast with over 25 years of experience caring for a wide array of tropical fish, including koi, goldfish bettas, cichlids and more! For me: Aquariums are like jello - there's always room for more!

Leave a Comment