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The Optimal Otocinclus Tank Size

The Optimal Otocinclus Tank Size
This post is written to the author's best knowledge and is not intended to be used in place of veterinary advice. In addtion, this post may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.

Are you thinking about buying some otocinclus catfish for your fish tank? This could be a great choice since they’re fantastic cleaners.

Many people choose to put these fish in community fish tanks. They help to eat algae and they’re peaceful fish that won’t bother their tank mates.

Whether you’re keeping these fish as community fish or if you’re planning to put them in their own tank, it’s important to meet their needs properly. You need to ensure that you keep these fish in tanks that are the right size.

Read on to learn about the best otocinclus tank sizes. You’ll also get related information that will help you to make good choices for your fish.

How Many Otocinclus Per Gallon?

Otocinclus catfish aren’t very big at all. They only grow to be between one and a half inches and two inches long at maturity.

Since they’re somewhat small, you might think that it’d be okay to keep one or two in a small fish tank. While these fish certainly don’t need to be kept in giant aquariums, it’s not wise to keep just one or two in a small five-gallon fish tank.

You see, these fish need to be kept in small groups. In the wild, otocinclus catfish live in large shoals of thousands of fish.

They’re not fish that do well by themselves. So determining how many otocinclus you should keep in the tank per gallon isn’t necessarily the best route to take.

To get the best results, you must keep at least six otocinclus in one tank. It’s possible to fit six otocinclus catfish in a 10-gallon fish tank comfortably.

Some people say that one otocinclus requires one gallon of space. Generally, it’s better to give otos more space than this so they don’t feel stressed.

Overcrowding a fish tank is not a good idea. This makes the fish tank dirtier, and water quality is very important when it comes to keeping these fish healthy.

How Many Otocinclus in a 10-Gallon Tank?

It’s recommended to keep no more than six otocinclus catfish in a 10-gallon fish tank. A 10-gallon aquarium will give six of these fish enough room to be comfortable.

Keep in mind that you also need room for decorations, plants, and other important things. Otocinclus catfish need hiding spots so they can be comfortable in a fish tank setting.

Don’t try to cram more than six fish into a 10-gallon tank. It makes it more likely that the fish tank will become dirty.

You want to ensure that the otocinclus catfish have more than enough room at the bottom of the tank. If you want to keep more than six otos in your tank, it’s better to go with a larger tank.

How Many Otocinclus in a 20-Gallon Tank?

Most experts agree that you can keep ten otos in a 20-gallon fish tank. A 20-gallon fish tank is a good size for these fish.

You can easily keep ten otos in a tank of this size while still having room for plants, little caves, and other types of decorations. This allows you to make your fish tank look nice while also ensuring that it’s very accommodating to the needs of the fish.

Enthusiasts say that keeping otos in a 20-gallon fish tank is much better than going with a 10-gallon tank. This is a bit of a larger tank, and it’ll allow you to keep a slightly larger group of fish together.

Once again, it’s best not to go overboard and try to cram too many fish in the tank. It’s much easier to keep the tank clean and the water quality high when the tank isn’t overcrowded.

Otocinclus Minimum Tank Size

The minimum tank size for otocinclus catfish is 10 gallons. If you don’t have room for a 10-gallon aquarium, it’s not recommended to keep otos in your home.

These fish are small, and a 10-gallon fish tank doesn’t take up a lot of space. For most, it’s going to be a very practical size to keep otocinclus catfish in an aquarium.

You don’t want to go smaller than a 10-gallon tank because these fish must be kept in groups of six or more. They live in large shoals in the wild and don’t do well when kept in very small numbers.

Even a pair of otos won’t do well in a five-gallon tank. You’ll notice that the fish will be stressed, and they will likely experience various health issues.

There Are Other Types of Otocinclus Catfish

The information above refers to common otos that you will find at the pet store. There are other types of otocinclus catfish that you might encounter that will have slightly different requirements.

For the most part, these otos are less common, and you’re less likely to find them in aquariums. This doesn’t mean that people never keep these fish in fish tanks, though.

The largest otocinclus catfish is known as the giant otocinclus. This is a fish that is native to the Amazon River Basin.

Normal otos only grow to be around two inches long in adulthood. Giant otos can reach four inches in length at maturity.

Since these fish are bigger, the minimum tank size is different for them. You need a 30-gallon fish tank to keep giant otos in a home aquarium.

Most otos are going to be small, so the information given to you earlier is accurate. There aren’t many otos that grow to be larger than two inches, but it’s still good to keep in mind that giant otos are out there if you’re interested in tracking them down.

Community Tank Sizes

Since these fish are good community fish, it’s common for them to be kept in aquariums with other fish. Whenever you’re putting together a community fish tank, it’s important to make sure that it’s more than big enough.

You don’t want to cram extra fish into a 20-gallon fish tank with your otos. These are peaceful fish that do well with various tank mates, but overcrowding the tank is bad.

If you want to keep otos in a community tank, a 29-gallon tank is likely the smallest tank that you should use. It might be more practical to use a tank that is much bigger than this, depending on how many fish you plan to add.

You need to make sure that all of the fish in the tank have more than enough room to swim and live comfortably. Also, otos need to live in planted aquariums, so you’ll need room for aquatic plants.

Take the time to research how much tank space the other fish need. Then factor in how much space the otos will need to stay comfortable in the tank.

Once you’ve determined that, you can decide the best minimum tank size for your community tank. In some cases, the best tank size might be 55 gallons or larger, but it comes down to how many types of fish you’re adding to the tank.

Otocinclus Tank Maintenance

Getting the tank size right for your otos helps to make tank maintenance that much easier. When you put them in a tank that’s too small, the water can get dirty very fast.

This makes it hard for the fish to stay in good health. It can stress the fish and make it tough for them to live in the tank.

Be sure to clean the tank regularly. It’s true that otos are cleaners, but you still need to remove leftover food debris and other organic material from the tank.

Regular water changes are also important. When caring for otos, it’s best to do weekly water changes.

You want to change 30% of the water each week. Keep up with this tank maintenance schedule, and your fish will have the best chance of staying healthy.

Final Thoughts

Now you know that otocinclus catfish need to be kept in 10-gallon fish tanks or larger aquariums. This is largely because these fish cannot be kept by themselves or in pairs.

Common otos aren’t very big fish. They only grow to be between one and a half inches and two inches long as adults.

Even so, they need at least 10 gallons of space in an aquarium. You must keep at least six otos in a fish tank since they’re shoaling fish.

These fish live in large shoals in the wild and won’t be comfortable in fish tanks if kept in groups that are too small. Six fish will be just enough to keep them happy in an aquarium.

Most experts say that it’s better to keep ten to fifteen of these fish in one tank. Ten otocinclus catfish can be kept in a 20-gallon fish tank without it being a problem.

There are some otos out there that are a bit larger than average. The giant otocinclus catfish can grow to be four inches long, but this is a less common fish.

If you want to buy giant otos, you’ll need to keep them in a 30-gallon fish tank or something larger. This makes sense due to their being double the size of common otos.

Remember to pick out a bigger aquarium than usual if you’re keeping otos in a community fish tank. You must have enough room to accommodate all of the fish.

Overcrowded fish tanks get dirty faster, and they can be a chore to take care of. Plus, overcrowding is known to stress fish, and it can lead to issues with disease.