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Why Are My Angelfish Hiding? (7 Common Causes)

Why Are My Angelfish Hiding? (7 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 very popular for a reason. Many people say that they’re among the best types of pet fish to buy.

If you just got some angelfish for your tank, then you’ve likely been enjoying them a lot. They aren’t hard to care for, but sometimes you might worry if you’re doing things right.

For example, you might be concerned about why the angelfish seem to be hiding. Is this an indication that something is wrong with this or is it normal behavior?

Continue reading to learn about some of the reasons why angelfish might hide. This should help you to feel more at ease, and you’ll also learn about whether there are any problems that you should try to fix.

1 – It Could Be Natural Behavior

pH Test Strips for Aquarium

Before you get too worked up, it’s important to know that hiding can be normal behavior for angelfish. Angelfish will choose to hide for certain reasons, and not all of them mean that something is wrong.

For example, in the wild, angelfish like to hide in the crevices of the coral reef. They’ll also sometimes hide out to get away from other fish using aquatic plants.

You likely have aquatic plants in your aquarium right now. If you don’t, then you really should since they help angelfish to feel more natural. When you find angelfish in the wild, they’re going to utilize live plants for many things.

The presence of the plants will help the fish to feel more at ease. Sometimes the angelfish might choose to hide from the other fish to get a break.

Having hiding spots in the tank can be a good way to prevent aggression issues from getting too bad. For instance, two male angelfish in the same tank might choose to fight quite a bit.

The males don’t get along very well, but if you keep them in a large enough tank, it won’t be as big of an issue. It’s also highly recommended to place hiding spots in the tank so that the fish can escape and get away from each other.

This is why having plants in the tank will be so imperative. It makes it so that the angelfish will be able to hide when they feel the need.

As you can see, it’s normal for angelfish to hide during certain situations. This doesn’t mean that it’s always normal for them to want to hide, though.

There are other things to consider when examining this topic. Below, you’ll find some of the more troubling reasons why angelfish will choose to hide, and many of these you’ll want to fix for the sake of the fish.

2 – Hard Water

Mineral Buildup from Hard Water

Hard water might be the reason why your angelfish are choosing to hide. You probably already suspect this, but your angelfish aren’t going to do well if you’re having them live in a tank with hard water.

In case you don’t know, hard water refers to water that has high levels of minerals such as calcium and magnesium. The water might also have high levels of sulfates and carbonates.

Angelfish vastly prefer soft water to hard water. If the water is very hard, then your fish might not survive that long.

This is why you’re supposed to treat the water that you put in the fish tank. If you’re very new to caring for fish, then you might not have known that you’re not supposed to use tap water.

Tap water must be conditioned if it’s going to be used to fill a fish tank. Otherwise, there’s a great chance that the water quality won’t be up to par.

If you changed the water in the tank recently, then you could have made a mistake. You might have forgotten to treat the water and the water in the tank is now too hard for the fish.

Thankfully, you’re going to be able to test the water to see what’s going on. You can buy a water hardness test kit and use it on the water to get all of the information you need.

There are two types of tests that you can buy to figure things out. You can get a strip test or a reagent test.

Either test will work for this purpose. You just need to figure out if the water is hard.

Once you have the necessary information, you’ll know if you need to soften the water. The easiest way is to use a reverse osmosis filter to remove the minerals and chemicals from the water.

You could also try adding peat moss to the tank, but buying a reverse osmosis filter is highly recommended. In the future, be sure to only put water in the tank that has been properly prepared for the fish.

3 – The Fish Is Experiencing Significant Stress

Child Near Fish Tank

Sadly, it’s possible that your fish could be experiencing significant stress. Sometimes fish will try to hide a lot and they will behave differently when they’re under a lot of stress.

Have you noticed that your angelfish is starting to look duller than usual? When these fish become stressed, they will often lose their bright colors and start to fade a bit.

This is problematic because fish are susceptible to diseases and infections when they’re in a stressed state. Why does this happen, though?

Simply put, angelfish wind up having their immune systems compromised when they’re under stress. If you want your fish to remain healthy, then it’s wise to keep it from experiencing too much stress.

You understand that stress is bad for the fish now, but you might not know what causes the fish to experience such stress. There are many things that can make the fish feel stressed.

For example, having someone tap on the glass constantly will stress the fish. If you have children in your home, then there’s a chance that they might do this to try to get the fish to look at them.

You should discourage your kids from doing this since it’s going to scare the fish. Sometimes pets will do something similar, and you’ll want to keep cats away from the fish tank due to how they’ll frighten the fish.

Loud noises will cause angelfish to be stressed quite a bit. If you have your fish tank in a very noisy portion of your home, then that might be a bad thing.

Don’t put your aquarium too close to things such as televisions and stereo systems. Even placing the aquarium in a noisy room where people talk loudly and walk around a lot might be problematic.

You want to find a spot for the tank where you’ll be able to observe the fish without disturbing them too much. Try to think of a logical spot in your home if you’re worried about stress.

4 – Water Parameter Issues

pH Test Strips for Aquarium

Water parameter issues can cause the fish to stress as well. You should know that you need to keep angelfish in water that has the right pH balance for them to thrive.

It’s necessary to keep checking the pH balance to ensure that everything is in the right range. It might have been fine last week, but something could have changed this week.

Testing the pH balance is as easy as using a simple pH testing kit. It doesn’t take long at all to get the information that you need.

You might discover that the pH balance is a little high or a little low. The ideal balance for keeping angelfish in a fish tank is between 6.8 and 7.8.

Always keep this in mind so that problems don’t pop up. An improper balance can lead to issues with ammonia, and too much ammonia in the tank can cause your fish to have problems breathing.

Another aspect of keeping the water parameters right involves checking the temperature of the water. Angelfish are hardy, but they do like the water to be pretty warm.

Ideally, you should keep the temperature of the water in the tank between 76 degrees Fahrenheit and 84 degrees Fahrenheit. Angelfish can tolerate temperatures that are a bit lower or higher than that, but they won’t be ideal.

Many angelfish enthusiasts will simply choose to keep the temperature of the water at a steady 80 degrees Fahrenheit or 82 degrees Fahrenheit. Remember that you have to keep the other fish in the tank in mind if your angelfish are part of a community tank.

5 – Crowded Fish Tanks

Platinum Angelfish in a Freshwater Aquarium

Crowded fish tanks can cause angelfish to want to hide sometimes. It’s not going to be a good idea to try to put too many fish in a tank at once.

Sometimes new fish tank owners will go overboard with the number of fish that they buy for one tank. You might get excited about the hobby, and this will cause you to want to buy all sorts of different fish.

While this feeling of exuberance is understandable, it’s not going to be practical. Crowding an aquarium is only going to make living in the aquarium unpleasant for the fish.

Fish need enough space to be able to do what they need to do. If you put too many fish in the tank, then it’s going to be a significant source of stress.

This is true for many different types of fish. As a general rule, fish don’t like living in crowded fish tanks.

You should try to do your best to keep the number of fish in the tank at a reasonable number. Consider how big your tank is and do your best not to make things too crowded.

Sometimes it might be better to go out and buy a bigger fish tank if you want to have a diverse community tank. A 55-gallon tank might not be enough if you’re planning to add quite a few different species of fish.

Perhaps you’d be better off with a 100-gallon tank if you have the right amount of space for it. Just do your best to make good choices and everything will likely be fine.

Also, remember that the fish will prefer more space rather than being put in a smaller tank. Keeping a few angelfish in a 30-gallon tank might be acceptable, but they’d likely be happier in a larger 55-gallon tank.

6 – Aggressive Tankmates

Angelfish in a Community Tank

Aggressive tankmates could easily cause the angelfish to want to hide. You might not be aware of this yet, but angelfish can’t be placed in community tanks with just any fish that you think look neat.

Sadly, angelfish aren’t going to get along with various types of fish. There are many fish that the angelfish will wind up either eating or bullying.

Angelfish are considered to be a semi-aggressive species. They can become territorial, and this means that it’s important to consider what fish you want to put in a tank with them carefully.

There are many great fish types that will get along well with angelfish. For example, guppies are some of the most well-known tankmates for angelfish.

You could also put fish such as dwarf gouramis, corydoras catfish, and mollies in the tank. Some people even like putting zebra loaches in community tanks with angelfish.

It’s just important to do some research ahead of time. This will allow you to learn if the fish that you’re thinking of adding to the tank gets along with angelfish or not.

You could wind up adding bigger, more aggressive fish to the tank by mistake. Then the angelfish would be the ones that are getting bullied.

They would try to get away from these large bully fish, and you’d see them hiding pretty often. This would be very stressful for the angelfish, and it’d be hard for them to thrive in such a community tank environment.

For this reason, you must pay attention to which fish you’re choosing for the tank. Do your homework and you shouldn’t encounter any issues that will prevent the angelfish from doing well.

7 – High Levels of Nitrite in the Water

Angelfish in Tank with Live Plants

High levels of nitrite in the water can be bad for the fish as well. You can use a reverse osmosis filter to solve this problem, but you might not have one.

The water won’t be in good condition if the nitrite levels get too high. You want the nitrite levels to stay between 5 and 10 ppm.

If things are very bad, then you might measure the nitrite levels at 20 ppm or higher. This is going to require immediate action to get things back to normal.

There are quite a few things that you can do to fix this issue. As mentioned, using a reverse osmosis filter is going to be the easiest thing to do.

You can also choose to add living plants to the water. This should be a simple way to lower the nitrite levels naturally.

Simply changing the water regularly should keep the nitrite levels in the right range as well. You might need to replace a lot at once if the nitrite levels are above 20 ppm, though.

So why would the nitrite levels in the tank rise? There are a few reasons.

This can happen when there is too much fish poop in the tank. It’s also likely to occur if you accidentally left some food in the tank.

Never feed your fish more food than they can finish. It’s dangerous for the health of the fish, and it can negatively impact your tank.

Decomposing plants can raise the nitrite levels as well. Taking care of the plants and picking out good ones should keep this from happening.

Is Hiding a Big Problem?

Hiding might not be a big problem depending on what is causing the angelfish to want to hide. If the fish are simply hiding sometimes as normal, then it’s nothing to be concerned with.

However, if the fish are hiding all the time, then that’s not going to be considered to be normal. Some issues will get so bad that the angelfish will choose to hide during feeding time.

If the angelfish won’t even come out during feeding time, then you know that the problems are serious. Typically, this only happens when you accidentally add a predator to the fish tank.

You might need to choose the tankmates for the angelfish more carefully. Or you might need to make sure that the tank has clean water.

Caring for angelfish is about paying attention to the little things. You need to feed the fish, and you also need to keep checking the water parameters.

The pH balance needs to stay in a specific range for the health of the fish. You also need to keep the water at the right temperature so that your angelfish will do well.

If you ignore these things, then the health of the fish will suffer. Even feeding the fish too much food can wind up causing issues with nitrite levels.

Keep all of this information in mind so that you can have a good experience with your angelfish. If you can prevent the fish from experiencing stress, then everything is going to be just fine.

Remember that angelfish will hide under normal circumstances sometimes. It’s simply not good for the angelfish to hide excessively because the water quality is poor or it has to worry about predators.