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Are Rainbow Sharks Aggressive? (And Will They Kill Other Fish?)

Are Rainbow Sharks Aggressive? (And Will They Kill Other Fish?)

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

Whenever you’re buying new fish it’s a good idea to learn about them. You want to make sure that you’re prepared to care for them properly.

It’s also important to consider whether bringing in new fish will be safe. For example, you might buy fish that are aggressive, and it won’t be good to put them in a community tank with certain other types of fish.

If you’re looking at rainbow sharks, you’re likely impressed by how pretty they are. They can be great fish to own in some ways, but are they aggressive fish?

Read on to learn everything you need to know about rainbow shark aggression. This should help you to make a good decision about whether these fish are right for your tank.

Rainbow Sharks Are Aggressive Fish

It’s true that rainbow sharks are aggressive fish. These fish are known to be quite aggressive, and this can make it tough for certain owners to deal with them.

They’re rather aggressive toward each other. You might want to only keep one rainbow shark in the tank due to this.

Rainbow sharks can also be aggressive toward other fish. They’re known for being territorial and don’t like it when other fish invade their territory in the bottom of the tank.

Since these are aggressive fish, you need to give them plenty of space. The minimum acceptable tank size for a rainbow shark is 50 gallons.

Do Rainbow Sharks Bite?

Yes, rainbow sharks are known to bite. You might see these fish biting other fish in the tank sometimes.

It’s not common for them to bite people, though. So you likely won’t get bitten by a rainbow shark when sticking your hand in the tank.

It’s not outside the realm of possibility that you could get bitten, but it’s simply unlikely. These fish are aggressive enough that they become territorial.

Sometimes rainbow sharks will bite other fish that enter their territory. These fish hang out at the bottom of the tank and will protect their turf by chasing and biting others.

Do They Have Teeth?

Rainbow sharks do indeed have teeth, and they use their teeth to break down food. These fish are omnivores that will eat both veggies and meat.

Sometimes rainbow sharks might use their teeth to bite other fish. This usually happens when rainbow fish are kept in fish tanks that are too small.

It’s also not wise to keep them in tanks with fish that they aren’t compatible with. So you need to make good choices that will help to keep your tank safe.

Don’t be afraid of getting bitten by rainbow sharks, though. It’s highly unlikely that a human would get bitten by a rainbow shark, and even if you did get bitten, you wouldn’t really get injured.

Are They Fin Nippers?

Fin nipping is something that rainbow sharks are known to do. They nip at the fins of other rainbow sharks, and this is why many people avoid keeping rainbow sharks together.

Sometimes rainbow sharks might nip at the fins of other fish as well. For example, they might nip at the fins of other fish that are aggressive or choose to enter their territory.

There are some mixed reports about fin nipping among rainbow sharks. Some reports say that these fish are among the worst fin-nipping offenders you can buy.

Others say that rainbow sharks aren’t that bad if you keep them in a big tank and ensure that there are enough hiding places. If you choose to buy these fish, it’s best to research compatible tank mates for them while also giving them enough space.

Do Rainbow Sharks Kill Other Fish?

It’s possible that a rainbow shark might choose to kill another fish. Some say that rainbow sharks aren’t so aggressive that they would kill other fish, but others note that these fish are omnivorous.

If a fish in the tank is small enough, it’s going to be eaten by the rainbow sharks. Also, these fish are aggressive enough that they will fight other fish that they see as a threat.

So it’s not impossible for rainbow sharks to kill other fish in the tank. This won’t happen if you keep them in a big enough tank and only put them in aquariums with compatible fish.

So you need to research things accordingly before proceeding. Even peaceful fish will sometimes eat other fish that are too small, so don’t let this information make you think that rainbow sharks are incredibly dangerous.

Why Is My Rainbow Shark Chasing Other Fish?

If your rainbow shark is chasing other fish, it could be a sign that the tank is a bit too small. A rainbow shark needs a 50-gallon fish tank as the minimum tank size.

It might need a larger tank if you’re planning to keep a lot more fish. Generally, it’s better to go with a larger tank than it is to stick with a tank that’s too small.

Sometimes chasing is normal behavior, too. Many rainbow shark enthusiasts have noted that these fish will chase neon tetras in the tank.

These fish are compatible with rainbow sharks and are fast enough to get away from them. So chasing isn’t such a big deal.

Chasing could be related to a territorial dispute. It’s not uncommon for rainbow sharks to chase other rainbow sharks in the tank if you’re trying to keep them in groups.

Why Do Rainbow Sharks Chase Each Other?

Rainbow sharks are known to be fairly aggressive toward each other. Some even recommend avoiding keeping rainbow sharks together in aquariums at all.

These fish often live in solitude, and you don’t need to keep multiple rainbow sharks in the same tank. They will often chase each other and fight for dominance in the tank.

It’s possible to keep multiple rainbow sharks in the tank, but you need a larger tank. It’s said that you need a minimum of 125 gallons of space when you plan to keep a small group of rainbow sharks.

So you’d need to commit to buying a large tank if you want to go this route. This is why so many people only keep one rainbow shark in a tank.

Can Rainbow Sharks Be Kept in Community Tanks?

It is possible to keep rainbow sharks in community tanks and have a good experience. Doing so can be tough if you don’t research compatibility first, though.

Rainbow sharks are aggressive, and this means that they can bother tank mates. You need to pick fish that can put up with them or fish that occupy a different area of the tank.

Thankfully, there are some good options that you can choose as tank mates for these fish. Harlequin rasboras, gouramis, plecos, goldfish, guppies, cherry barbs, and more can be utilized in community tanks with rainbow sharks.

So you have many choices that you can consider when putting together a community tank. Remember to give the rainbow sharks more than enough room and be sure to put hiding spots in the tank to keep everything safe.

What to Do with an Aggressive Rainbow Shark

Typically, rainbow sharks will only be overly aggressive when something is wrong in the tank. If your rainbow sharks are aggressive, it’s likely that the tank is overcrowded or you’re keeping the fish in a tank that’s too small.

You might need to move the fish to a larger tank. It might be good to try adding hiding spots to the tank as well.

Putting caves and aquatic plants in the tank can be very useful when keeping rainbow sharks. These fish like plants such as java ferns and hornwort in the tank.

Caves are great for these fish because they like to hang out in them and will wind up just defending the caves that they choose. If there’s enough room and the tank has hiding spots, it’s not that hard to mitigate rainbow shark aggression.

Final Thoughts

You’ve learned a lot about rainbow sharks now. It should allow you to make wise choices when setting up tanks for these fish.

They are indeed aggressive fish, but you can deal with that aggression by making good choices. You need to give the fish enough room in the tank so they will feel less territorial.

It’s also important to choose only compatible tank mates for the tank. Rainbow sharks won’t get along well with certain types of fish.

Adding hiding spots, such as caves, to the tank will make a huge difference. It’s also good to have aquatic plants in the tank.

You can have a good experience caring for these fish when you put in the effort. They’re not the easiest fish for beginners, but you don’t have to shy away from rainbow sharks simply because they’re aggressive.

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