How To Stop Angelfish Bullying – 4 Top Tips!

Angelfish are a beautiful and relatively peaceful aquarium fish, but they can also be aggressive. This article will discuss angelfish bullying behaviour and what you can do to prevent it.

Angels may bully other angelfish for any number of reasons: because they are bigger or smaller than the bullied angelfish, because they have a different coloration, or just for no reason at all. But regardless of the cause, angelfish bullying is a problem that affects many people who keep this species in their aquariums. 

How to stop angelfish bullying? Fortunately, there are steps you can take to stop angelfish bullying or prevent it from even starting.

These tips are all you need to know!

Tip 1: Give Them The Right Environment

Tank Size

You need to ensure that your tank is big enough for your angelfish or angelfish group. The recommended minimum angelfish tank size is about 20 gallons per angelfish – they are big and very active fish and prefer a lot of space to swim around in!

A larger tank is required not only because they prefer to have a lot of space to swim in, but because Angelfish can be very territorial. Angelfish like to have their own space and if the tank is too small for them they will become stressed and will see other fish as competitors to their space, breeding spots and food supply. This leads to aggressive behavior and to bullying.

Hiding Spots

Angelfish also require a well decorated tank – and by that I mean one that has lots of plants, rocks and ornaments that provide plenty of hiding spots for angelfish. This again relates to their territorial nature they love to make a few hiding places their own so if there’s plenty of them they shouldn’t need to compete over them – it also gives them a place to go for respite from any other troublesome tank mates.

Water Quality

The angelfish bullying behavior can also be caused by water quality issues. If you use tap water make sure it is dechlorinated before putting it into your aquarium as chlorine and chloramine in tap water are toxic for angelfish. (source)

In addition, angelfish need clean water so regular cleaning of the aquarium (about 25-50% weekly depending on bioload), gravel vacuuming and filter maintenance is important.

Tip 2: Feed Them Well

When you think about it, this one is obvious – have you ever been a bit grumpy and irritable when really hungry? I know I have! Your angelfish are no different. If you aren’t feeding you fish often enough they will become stressed. In the wild, survival of the fittest dictates that the scarcity of food supply will automatically lead to an increase in competitiveness as fish fight over what food is available – the same holds true in your aquarium.

You also need to ensure that you are giving your angelfish the right sort of food. Again like us humans, a poor diet can and will lead to health problems which again causes your fish to feel stressed and increases their aggression levels. Make sure that you feed your angelfish a varied diet that can include good quality flakes and/or pellets and also the occasional live, frozen or freeze dried invertebrates like brine shrimp, daphnia, or bloodworms.

Feeding angelfish the right sort of food will ensure that they have a good quality of life and are generally less likely to become aggressive.

tray of frozen brine shrimp
Frozen brine shrimp are an excellent source of food for an Angelfish

Tip 3: Male to Female Ratio

If you are keeping several angelfish you need to ensure that you have a reasonable number of males to females.

If you have too many males in comparison to the females you may find that the males pester the females excessively! It’s also highly likely that the males may start to become aggressive towards each other as they will compete over the female.

Too many females in a tank will also likely lead to bullying behavior – as the females will feel like they have to compete over space in which to lay their eggs.

As stated above, having plenty of space is paramount for your angelfish as is having a good balance of males and females – i’d aim for having an equal number of males to females or another option would be having a 2:1 ratio in favor of the females.

Tip 4: Dither Fish

Dither Fish

“Dither Fish” is a term used to describe fish that are kept in an aquarium in order to aid normal social behaviour and prevent/reduce timidity or aggression in other fish within the same tank.

A school of smaller fish like tetras or danios are excellent “dither fish” to add to an aquarium housing angelfish. The fish are small enough that the angelfish don’t see them as competitors and they are fast and nimble enough to cope with the angelfish’s attempts to chase them and the chasing of these fish acts as a distraction and reduces the likelihood of the angelfish becoming aggressive to each other.

A school of Zebra Danios would be ideal "dither fish"


Is it normal for angelfish to fight?

Yes, it is very common for angelfish to become aggressive with other angelfish as they all have a very strong and powerful territorial instinct. It is therefore important that angelfish are kept in an aquarium of sufficient size and this is especially true if you are keeping angelfish with other fish species.

Why is my angel fish attacking my other angelfish?

There could be a number of causes behind this such as a lack of food, not enough space or hiding spots in the tank, the fish could be ill or stressed. Ensure that you have given your angelfish enough space for them to feel comfortable, ensure they are living in water conditions that suit them, that they are fed well and look for any signs of illness. I think the most likely reason would be a lack of space – people tend to underestimate just how much space an angelfish needs to feel happy!

Why is my angelfish being aggressive?

The main cause of this is likely to be a lack of space. If the tank is too small angelfish will become aggressive and very territorial, they will feel like they have to compete for everything – breeding areas, hiding spots and food.

Other possible causes include illness (make sure you check regularly for signs of illness with all fish that you keep), poor water quality (how often do you check pH levels and do water changes?) and poor diet – all of this can make your angelfish stressed and angry!

How can you tell if angelfish are fighting?

It can sometimes be difficult to tell whether your angelfish are fighting or whether the behavior they are exhibiting is actually mating behavior.

It is common if your angelfish are pairing up for the male to follow the female around the tank and another example of mating behavior would be lip locking (or “kissing” for you romantics!)

Fighting behavior is very different.

Rather than gently following each other around, an aggressive angelfish will chase the other repeatedly and at top speed.

Rather than “kissing”, an aggressive angelfish is likely to nip at the fins or body of the other fish and will even hit them by flicking their tails at each other!

How To Stop Angelfish Bullying - Conclusion

Bullying and fighting is common when keeping angelfish but there are things you can do to stop it or even prevent it from happening in the first place. The most important thing is that you are giving all of your fish the conditions they require in order to thrive – the right size of tank, the right water quality, the right kind of diet, the right tank mates and so on. By following the top tips covered in this article you will have the best possible chance of stopping your angelfish bullying!