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Why Are My Angelfish Suddenly Aggressive?

Why Are My Angelfish Suddenly Aggressive?

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.

Keeping angelfish in an aquarium is great. They’re lively fish and they look really neat overall.

People are drawn to their vibrant colors, and they’re also not too hard to take care of. Generally, they’re regarded as some of the prettiest fish that new aquarium owners can purchase.

If you’ve been caring for angelfish for just a little while, then you might be worried if the fish suddenly start to seem more aggressive than usual. If everything was going fine for several weeks, then why would the fish start acting differently?

Keep reading to learn more about angelfish aggression. It should help you to get to the bottom of what is going on.

Angelfish Are Normally a Bit Aggressive

It isn’t unusual for angelfish to display aggressive tendencies. If you were caring for young angelfish, then they might have suddenly become more aggressive upon reaching maturity.

Of course, it’s also possible that something happened that brought the aggression out of the angelfish. Angelfish aren’t necessarily the most aggressive fish that you can own, but they will chase other fish and fight.

Many angelfish enthusiasts note that they’re mostly peaceful. Typically, angelfish are only aggressive in certain situations.

So while it’s normal for angelfish to be a bit aggressive, there’s likely something going on if the fish seem particularly aggressive in your tank. Below, you’ll discover some of the reasons why angelfish will be aggressive.

Territorial Disputes with Other Fish

One of the more common reasons why angelfish will show signs of aggression has to do with territorial disputes with other fish. The angelfish might be in a tank with other fish, and if things are a bit crowded, then it’s likely that some fighting or chasing will occur.

An angelfish might feel the need to try to fight off or chase off other fish to defend its territory. This might not be too bad of a situation, but it could be if you didn’t do a good job of picking other fish that are compatible with angelfish.

You’ll find that angelfish will eat other fish if they’re small enough to be eaten. This is why you must pick fish that are roughly the same size or slightly larger than the angelfish.

The tankmates of the angelfish need to be able to withstand the aggressive nature of the angels. If you don’t choose wisely, then you’re not going to have a very peaceful tank.

Note that you shouldn’t put fish in fish tanks that are too small. If the fish feels crowded, then more fighting is going to occur.

Try to pick out a fish tank that is more than big enough for the fish that you want to purchase. Keeping a few angelfish and several other fish in a small 29-gallon tank likely won’t be a good idea.

Two Male Angelfish in the Same Tank

As an aquarium newbie, you might not be aware that two male angelfish won’t get along well. Some people don’t get told this when buying the fish, and it leads to severe aggression issues.

Male angelfish will fight each other quite a bit. They will squabble over territory, potential mates, and many other things.

The fighting between two males can get very serious at times. It wouldn’t be unusual to see two fish injure each other while fighting.

It’s even possible for one male angelfish to kill the other. This is highly unlikely, but it has happened when two fish have been placed in a small enough tank.

You can keep two males in the same tank if the fish tank is very large. This gives the fish enough room to spread out and it should reduce the number of aggressive confrontations.

Even so, it would be easier to only keep one male angelfish and one female angelfish in the same tank. If you want to have an easy time, then you should just stick to that arrangement.

If you simply must keep multiple angelfish in the same tank, then ensuring that there are aquatic plants in the tank might help. It gives the angels hiding spots so that they can get away from each other.

How to Solve Aggression Issues

You don’t necessarily solve aggression issues because you can’t change the nature of the angelfish. Some suggest that changing the water in the tank a bit less frequently will help to keep the fish calmer.

This doesn’t mean that you can allow the tank to become dirty, though. That would be unhealthy for the fish, and it would only lead to more issues.

Changing the water out biweekly might be a solid idea, but you’ll need to change out a higher percentage each time if you go this route. You should still be able to change the water out weekly if you prefer doing that since it’s not going to make a huge difference.

Avoid putting two males together in the same tank if you can. If you have to keep two males together, then be sure that you have a fish tank that is more than large enough.

Putting other fish into the fish tank with the angels will be fine, but you’ll want to pick the fish carefully. If you put small fish in the tank, then the angelfish will bully them and eat them.

To get the best results, pick compatible tankmates such as guppies and corydoras catfish. They’re big enough to keep up with the angelfish, and the aggression issues won’t be as big of a deal.

Final Thoughts

You’ll have a better idea of why angelfish can suddenly become aggressive now. They might fight with each other, and they might wind up fighting over territory with other fish as well.

Sometimes angelfish can be very aggressive, and they will eat other fish in the tank if they aren’t big enough. Picking compatible tankmates will be of the utmost importance.

You can’t stop angelfish from being aggressive. That is just how the fish are, but they will be relatively peaceful if you take their nature into account.

Give the angelfish a big fish tank, ensure that you have aquatic plants that the other fish can use as hiding spots, and be sure to feed the fish enough food. If you’re doing your best, then keeping angelfish in your tank won’t be a problem.