Are Rasboras Fin Nippers?

Rasboras typically aren’t fin nippers. However, it’s possible they can nip the fins of their tank mates when their aquarium doesn’t provide the ideal conditions for them to thrive. 

Because rasboras aren’t known to be fin nippers, it can signify that something is wrong when they do start nipping each other’s fins or the fins of other fish. Therefore, knowing how to properly care for rasboras is crucial if you want them to be happy and thrive in their new environment.

Do Rasboras Nip The Fins Of Other Fish?

Rasboras are beautiful and exciting fish. There are many kinds of rasboras; some are easier to take care of than others.

However, one thing most rasboras have in common is that they are typically peaceful fish that rarely nip the fins of other fish. Therefore, rasboras are good companions for slower fish, like bettas.

When you see your rasboras nipping each other’s fins or the fins of other fish, it usually signifies something wrong in their environment. Rasboras will only start nipping the fins of other fish if they feel threatened or the tank conditions aren’t suitable.

There are five primary reasons for rasboras nipping fins. First, you must inspect their tank conditions to discover the reason for their sudden behavior change. So, why do rasboras become fin nippers?

Group of Harlequin Rasboras

1. The Rasboras Feel Territorial

While some fish species prefer to stay at the bottom of your aquarium, rasboras usually hang around the top. Since they are so small, this is where they feel the most comfortable.

Therefore, rasboras may attack other fish who enter their swimming space if they feel threatened. For example, suppose you add another fish species to the aquarium that likes swimming in the top water. In that case, the rasboras may feel threatened and attack them.

Fortunately, not many other fish like swimming close to the top, so seeing a rasbora attacking another fish is scarce. They don’t really swim to the bottom of the tank and will rarely attack other fish or nip their fins at the bottom.

Suppose you notice your rasboras fighting with other fish for the top part of the aquarium. In that case, you must separate these two species. If only one rasbora is attacking, you can remove it from the tank to see if that solves the problem.

2. The Tank Conditions Aren’t Ideal For Rasboras

Another reason why rasboras may suddenly start acting aggressively towards other fish is if their tank conditions are no longer ideal. This can be the result of various things, such as:

  • The tank is too small for the number of fish.
  • The water quality (temperature and pH levels) isn’t suitable for the rasboras.
  • Too many fish in the tank compete for the same food or shelter.
  • The rasboras aren’t getting the right kind of food.

To prevent the rasboras from becoming aggressive towards other fish, you must ensure that their preferred tank conditions are met.

Rasboras require a tank size of 10 gallons or more and must be kept in schools of 7 or more fish. They also require water with a pH of 6.8 – 7.8, and the temperature should be between 75 and 80°F.

Rasboras are also omnivores. While they aren’t fussy about their diets, they may become aggressive if they aren’t fed the proper nutrients.

If you notice your rasboras nipping other fish’s fins, you must check that the tank conditions are still acceptable for keeping them. If not, adjust the water quality and feeding times, so the rasboras feel more at ease and stop their aggressive behavior.

3. There Aren’t Enough Rasboras In The Tank

Yet another reason why rasboras may start nipping the fins of other fish is if they feel threatened. This is most often because there aren’t enough rasboras in the tank, and they feel they will be targeted.

Since rasboras are schooling fish, you must keep at least seven rasboras in a tank for them to feel secure. If not, your rasboras will stress about their school being too small and may show aggressive behavior.

Furthermore, you must ensure that the tank can house enough rasboras for them to feel safe without needing to compete for food or shelter. For example, if you have seven rasboras in the tank, a 10-gallon tank will be sufficient. However, the more rasboras you have, the bigger the tank you need.

People often keep rasbora schools in tanks of more than 20 liters to feel safe and sheltered without fighting for dominance or food.

4. There Are Too Many Male Rasboras In The Tank

If you see rasboras attacking each other, it can signify that too many males are in the tank. If the males outnumber the female rasboras, they will attack each other to establish dominance in the tank.

Moreover, the males may also attack the females when trying to mate, even if the tank conditions aren’t suitable for mating. In this case, the male rasboras will chase the females and may also nip their fins.

To prevent male rasboras from fighting for dominance or attacking the females, you must ensure that there are at least three females for every male. For example, if you have seven rasboras, there can be one or two males at the most, and the rest should be female.

Your rasboras are usually sexed at the pet shop to ensure that there aren’t too many males in a tank. Therefore, you can add more females if you suspect that this is the cause of the fighting or fin nipping.

5. Rasboras May Attack Sick Fish

Finally, your rasboras may attack and nip the fins of sick or injured fish. This is a natural response as the rasboras will try to banish the sick fish to prevent it from infecting the population.

Furthermore, the rasboras will attack an injured fish if they feel it risks the group’s safety. Therefore, if you notice one of your fish is injured or sick, you must remove it from the tank for quarantine.

If not, the rasboras will likely attack it until it is dead if they fear that it will cause the rest of the group harm. Once you have removed the sick fish, treat it and the tank to prevent the other fish from getting sick.

These are the main reasons your rasboras may start nipping the fins of other fish. However, this behavior is rare with rasboras. So you can feel assured that they won’t cause any problems with each other or the other tank fish if they are happy.

Are Any Rasboras Known For Fin Nipping?

There are many kinds of rasbora fish. Fortunately, none of them are known to nip the fins of other fish and therefore shouldn’t cause you any problems if you keep them happy and healthy and in a clean tank.

These are some of the most popular rasboras to keep in an aquarium:

  • Harlequin rasboras
  • Galaxy rasboras
  • Chili rasboras
  • Clown rasboras
  • Scissortail rasboras
  • Blackline rasboras
  • Dwarf rasboras

None of these rasboras have the tendency to nip the fins of other fish or bully them. However, if you notice that your rasboras are nipping the fins of other fish, one of the reasons above is likely the cause.

Which Fish Are Fin Nippers?

While rasboras are unlikely to nip the fins of your aquarium fish, there are other species that aren’t as friendly. You should keep these fish out of community tanks, especially tanks with smaller fish like rasboras, or slower fish like bettas.

Examples of fin nippers are betta fish, livebearers, neon tetra, pea puffers, and pearl gourami. These fish are known to nip the fins of other fish and may injure or even kill some of your rasboras if they continuously nip their fins.

What Fish Can You School With Rasboras?

Because rasboras aren’t known for fin nipping, you can keep them in a tank with many other types of fish. However, you must ensure that these fish have the same tank requirements (water pH and temperature) as the rasboras.

People often pair rasboras with bettas, rainbowfish, tetras, or loaches. Furthermore, you can keep your rasboras in a tank with other aquatic animals, like snails and shrimp.

Rasboras are typically great housemates and shouldn’t cause any problems with other types of fish if their tank conditions are met. However, if you notice one of your rasboras bullying or attacking another fish, it may be best to remove that fish from the tank.


It’s extremely rare for rasboras to nip the fins of other fish. They will only resort to this behavior if something is wrong in their environment. For example, if the water conditions aren’t right or there aren’t enough females in the tank, the rasboras may start to nip each other’s fins.

When you notice this behavior, you must act quickly to determine the cause of the problem and solve it. For the most part, however, rasboras are delightful fish and shouldn’t cause any problems in your tank with each other or other schools.