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Why Are My Angelfish Dying? (8 Common Causes)

Why Are My Angelfish Dying? (8 Common Causes)

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.

Angelfish are among the most popular types of pet fish. This is because they’re so pretty and easy to care for overall.

The fact that angelfish are generally easy to take care of can lull you into complacency, though. If you don’t take care of the fish properly, then they can die.

If you came home from work one day and discovered that your angelfish died, then you’re likely upset. You might even be confused about what happened to the fish.

Why are the angelfish dying? Is there a good way to get to the bottom of what happened?

Keep reading to learn about some of the common reasons why angelfish die. It should help you to figure out what might have gone wrong in your situation.

1 – Water Quality Issues

Angelfish in Cloudy Water

The most common reason why angelfish die involves water quality issues. You should already know that you need to keep the water at a specific pH balance for the sake of the fish.

When you’re caring for the most common angelfish, they’re going to need the pH balance to stay between 6.8 and 7.8. Other angelfish might have slightly different pH requirements.

If the pH level of the tank gets thrown off, then it could kill the fish if you don’t correct the issue. This is why it’s imperative to test the water in the tank using a pH testing kit every so often.

You can buy chemicals that will allow you to raise or lower the pH level of the water. It’s likely going to be smart to keep some of these chemicals on hand for when you need to balance things out.

Aside from pH balance issues, it could be that the temperature of the water wasn’t right. Common pet angelfish need the water to stay between 78 and 84 degrees Fahrenheit.

The fish should be able to survive if the water is a bit cooler or hotter. However, significant fluctuations can harm the fish. Cold water could easily kill the fish, and this is why you need to use a reliable heater.

So long as you do your best to check the water quality, it should be unlikely that you’ll have the fish die on you. Sometimes things do happen that you might not notice right away, though.

For example, your heater could die, and this could cause the water in the tank to rapidly cool. Your filtration system could stop working, and this might make it so that the fish won’t have the oxygen that they need.

Do your best to check the tank and keep an eye on the equipment. If you catch things fast enough, then you can replace heaters, filters, and other things to keep the fish safe.

2 – Disease

Have you considered whether the angelfish were sick when you purchased them? It’s possible that the angelfish could be diseased in some way, and this caused them to die prematurely.

You can look for physical signs of illness in the fish. For example, the angelfish might have rotten fins or they could be bloated in some way.

Other signs include missing patches of skin, white specks on the body, and fluffy growths. You should try to observe the fish before you buy them from the store to try to ensure that you’re getting healthy fish.

Sadly, the conditions that the fish are living in at pet stores won’t often be great. You’ll usually find that the fish are kept in tanks that are far too cramped, and this can lead to various issues with sickness.

Look at the water in the tank at the pet store. Does it appear dirty?

If the water quality doesn’t look too good, then that’s not a positive sign. You should also try to see if the fish seem sluggish or not.

A sluggish fish is more likely to be sick than one that appears to be lively. Do your best to pick out a fish that appears to be healthy so that it won’t die prematurely.

If you notice that some of your fish seem sick in your home aquarium, then you can try to contact an exotic veterinarian. In some cases, they might be able to treat the fish if the sickness isn’t too bad.

3 – Stress and Shock

Several Angelfish in a Tank

You might not think that stress could be responsible for killing your fish, but it’s certainly possible. There are various conditions that can cause fish to experience stress.

Sometimes fish live in such cramped environments at the pet stores that they will go into shock when they enter a clean tank in your home. If the fish isn’t in the best condition, then the shock could potentially kill it.

There are situations when fish will die despite your best efforts. You can try to limit shock and stress issues as much as you can.

Don’t crowd the fish tank too much. Fish aren’t going to like living in overly cramped environments, and you can sometimes cause a fish to go into shock by keeping it in a small tank with too many fish.

Not having plants in the tank can cause a fish to experience stress, too. Fish will feel more at ease when there are aquatic plants that they can use to hide.

4 – The Presence of Dead Fish

Sometimes fish die, and this can happen for many reasons. Fish can even die of old age when you do a good job of caring for them.

When a fish dies, it’s important to remove it from the tank promptly. The presence of the dead fish corpse is going to be detrimental to the other fish in the tank.

Even if you think that the other fish will just eat the dead fish, it’s not wise to leave it in there. A decaying fish will release toxic chemicals that will pollute the fish tank.

This is going to be very bad because having too much ammonia in the tank could eventually kill your fish. Try to pay enough attention to the tank that you’ll notice when one of the fish dies.

That way, you’ll be able to get your net and scoop the dead fish out. It’ll help to protect the living fish, and you won’t have to worry quite so much.

5 – Food Issues

Angelfish and Discus Feeding

There are a few different ways that food can cause fish to die. The first and most obvious one is that not feeding the fish will eventually kill it.

Angelfish can actually go for a while without being fed. The fish should be able to survive for three days without eating food.

A healthy adult angelfish will be able to live for a week without eating. This doesn’t mean that you should get lazy about feeding your fish, though.

Feeding the fish is important because it gives them energy. It allows the fish to stay healthy by ensuring that they have the nutrition that they need.

You should be feeding your angelfish once or twice a day. It’s easiest to just set a schedule and feed the fish at the same time every single day so that you get into a routine.

If you neglect the fish for a long period of time, then it’s going to die. You can’t avoid feeding your fish for over a week and expect it to be alive.

An angelfish could also die from eating food that it’s not supposed to. There are many food types that aren’t meant for angelfish to consume.

Only feed the angelfish recommended food items that are meant for angelfish. You can feed the angelfish special fish flakes, shrimp pellets, frozen shrimps, and even some types of live worms.

You also need to know not to go overboard when feeding the fish. Feeding a fish too much can lead to complications.

Try to give the fish only as much food as it can finish in two or three minutes. This should allow you to keep the fish healthy while also ensuring that it has enough to eat.

You also need to avoid overfeeding the fish because excess food could contaminate the water. If you ever make the mistake of feeding the fish too much, then you should scoop the excess food out.

Use a net or a siphon to take out the excess food that the fish didn’t touch. You’ll likely not have to bother with this too often once you get used to how much food you’re supposed to give the fish.

6 – Incompatible Tank Mates

Angelfish in a Community Tank

Of course, people often keep many different types of fish in their aquariums. You might have several species of fish living together with your angelfish in a large fish tank.

This is fine, but it’s only fine if you’ve done your homework. You need to ensure that you’re picking compatible tank mates for the angelfish.

If you put larger fish into the tank, then they might wind up trying to eat the angelfish. There are certain types of aggressive fish that could try to bully the angelfish, too.

This could cause the fish to die in many different ways. Fighting the fish could cause it to sustain injuries that will eventually kill it.

It’s also true that the fish could become so stressed by the situation that it will eventually die. You need to be truly careful when putting new fish into your fish tank.

7 – Angelfish Fighting Each Other

In case you don’t know, male angelfish don’t really like each other. If you put two male angelfish in the same tank, then they’re going to fight.

Males will fight for many reasons, and they often fight to try to win the approval of the female angelfish in the tank. They’ll fight over territory, food, and mates.

This is all very annoying because the males will likely injure each other when fighting. Typically, two male angelfish won’t fight to the death, though.

It can happen when the males are placed in a small enough tank. This means that you shouldn’t assume that your males didn’t kill each other if you find them dead in the tank.

Many would say that it’s better to avoid putting two males in the same aquarium. It would likely be easier to just place one male and one female in the tank.

There are fish enthusiasts who have been able to make males live together in relative peace. This is usually best attempted when placing angelfish in very large tanks such as 100-gallon tanks.

The fish will have more space and will be able to stay away from each other for the most part. For some aquarium owners, finding enough space for a 100-gallon tank won’t be practical.

There are way larger home fish tanks out there, but many people have limited space available for aquariums. Just keep this in mind so that you can plan ahead.

8 – Old Age

Angelfish Close Up

If your angelfish are very old, then the fish might have just died due to old age. This can happen when you do a very good job of caring for angelfish.

Angelfish have the potential to live for as long as 10 years in a fish tank. Not every angelfish will live this long, but some can with the proper care.

If you do your best to feed the angelfish properly, and you care for the tank really well, then your fish might be lucky enough to live this long. In this situation, it was just time for the fish to go.

You can go out to get a new angelfish and do your best to care for them as well as you did your old one. Of course, if your angelfish is only a few years old, then it likely died for another reason.

How Can You Turn Things Around?

Turning things around and protecting your angelfish involves making necessary changes. There might be certain things that you’ll need to start doing differently for the sake of the fish.

First, you’ll need to do some detective work to try to determine what went wrong. If you can pinpoint how the fish have been dying, then you might be able to correct the mistakes that were made.

For example, if the pH balance of the water is thrown off, then you can endeavor to check the pH balance more often. This way, you’ll be able to keep the fish in a safer environment.

Keeping your tank clean and caring for it properly is really all you can do. You’ll also need to feed the fish properly and try to look out for signs of sickness.

If you’re doing everything right, then the fish should survive for quite some time. There can still be issues that will be beyond your control, but you can try to keep the fish alive to the best of your ability.

Those who are very perplexed by what is going on might need to talk to an exotic veterinarian. Veterinarians can give you advice about caring for the fish that you might not have considered.

Angelfish Are Hardy

Two Angelfish Feeding

The good news is that angelfish really aren’t that hard to care for. They’re hardy fish that can go without eating for a few days without it being a big deal.

Making a few mistakes will be unlikely to kill the fish. This should give you time to learn so that you can start doing everything right.

Angelfish have long been considered to be great fish for beginners. They’re just hardy enough that most people will have a good experience caring for them.

If some of your fish die, then that can be very disconcerting. However, mistakes do happen, and you can learn from them.

You can do your best to start taking a different approach so that the fish will do better under your care. Ensure that you don’t give up if you really love having angelfish in your tank.

Final Thoughts

You’ve learned about many different reasons why angelfish might die. The most common reason why angelfish die is that the water condition is not proper.

Having the pH balance or the temperature be thrown off will negatively impact the fish. If you can’t fix issues with the tank, then the fish will eventually die due to poor water conditions.

Stress and shock have been known to kill fish, too. Sometimes fish get overly stressed when placed into tanks that are too small.

Sickness has the potential to kill fish, and sometimes you’ll buy sick fish from the store. Try your best to pick out healthy fish and avoid buying fish from pet stores that keep the fish in poor conditions.

Improper tankmates could be eating your angelfish, or they could at least hurt them in fights. This could cause the fish to die due to succumbing to injuries.

Male angelfish might even kill one another under the right circumstances. You should probably avoid putting two males in the same tank.

You know what can kill your angelfish, and this gives you the power to turn things around. Take everything that you learned and use it to care for your angelfish better than ever.

Even if you have to go out to buy new angelfish, at least you’ll have confidence that you can do better this time. It takes time to get everything down when you’re new to keeping aquariums, but it’s a satisfying hobby that is worth the effort.