Why Is My Angelfish Hiding?

Freshwater angelfish are one of the more unique and beautiful species of fish in the hobby, so it can be frustrating when your angelfish hides all day long.

While most fish will spend some time seeking cover in their natural habitat, it might be for one or more reasons within the aquarium. Everything from stress levels to whacky water parameters can force a fish to seek seclusion from tank mates and you.

Why is my angelfish hiding

We have learned to observe our cichlids over the years to help better care for them, and if we find an angelfish hiding behind the filter, we tend to take notice.

Finding the reason for hiding can alert you to issues within the water or the fish itself. Knowing what to look for and how to address it can keep your aquarium and all the fish within it healthy and safe.

Let us share some insight into the following to better prepare you for when your favorite angelfish is hiding behind plants or other decors:

  • Reasons why angelfish are always hiding
  • Why hiding spots are beneficial to your angelfish
  • Answers to commonly asked questions that you may also have

Why Is My Angelfish Hiding?

Natural Behavior

Before you get too concerned that your fish seems to be always hiding from view, keep in mind the fish’s natural habitat in South America.

Waters like the Tapajos River (the fifth-largest tributary of the Amazon River and one of the native homes of freshwater angelfish) are somewhat murky and filled with exposed roots, tall plants, and other vegetation that provide natural hiding spots.

While these omnivores can use these conditions to ambush smaller aquatic animals for food, their body design also allows them to move through this debris to avoid becoming prey items for larger fish found in the rivers and tributaries.

These hardwired instincts translate to the fish tank, where your angelfish hides all day within plants and other decors you provide. New arrivals will use cover to reduce stress levels as they adjust to their new environment.

Established angelfish residents will use hiding places to get away from other fish that are overly aggressive, to spawn, or to feel safe from perceived predatory threats (including movements and sounds from outside of the aquarium).

The key for you as a keeper is to identify when this natural behavior indicates something else. Our biggest tip in this regard is to observe your fish often to establish when something is off with how they act. It should not take long to determine when your pet is behaving sluggish or timid, signs that will require further inquiry.


Sickness could be why your angelfish is hiding behind the filter or among those Amazon sword plants you just placed in the fish tank. Aquarium fish can become ill due to several bacteria, fungal, and viral infections. Freshwater angelfish that are sick will often stop eating and hide because they are stressed.

An example of this would be ick, a common disease among aquarium fish that manifests white spots that look like salt granules, scratching behavior, and reduced eating. Other illnesses seen among angelfish include columnaris, hexamita, and swim bladder disease.

Fortunately, you can find ways to prevent things like ick, or manage these diseases once identified. Quarantining all new fish for ten days in a separate tank helps, as does cleaning any used decor before adding to an aquarium. If you believe your freshwater angelfish are healthy, there is likely another reason it is always hiding.


It could be an instinctual reaction when you see angelfish hiding behind plants. In their natural habitat in South American waters, angelfish can be prey for larger fish, black caimans, and an occasional bird. Species of fish that might prey on freshwater angelfish include arapaima, goliath catfish, peacock bass, pirarucu, and red or yellow-tailed barracuda.

Those natural reactions will transfer to the aquarium setting, even in specimens several generations removed from the wild. Even if you do not keep species large enough to eat your angelfish, other aggressive fish species can chase and nip at them. They can also perceive foot traffic, curious children, and loud noises outside of the tank as a dangerous predator.

Your pets will seek hiding places to reduce their stress levels. Having walls and plants to hide among gives fish a natural sense of security. If there are no aggressive tank mates and outside stimulants, something else is likely causing this behavior change.

Aggressive Tank Mates

While your freshwater angelfish are cichlids and can be aggressive under certain circumstances, they can be victims of fish bullying. In their natural habitat, larger fish (including other angelfish) may become aggressive toward angelfish over food, territory, or hierarchical displays. These behaviors can transfer into the aquarium setting for many of the same reasons.

If your angelfish hides all day, it might be trying to avoid aggressive fish in the tank that are chasing it or nipping at its fins. It stays hidden behind aquarium equipment or decorations to provide a more defensible position and to feel safe. You can take steps to reduce stress levels in the aquarium.

Removing problem tank mates is one solution, and transferring your angelfish into a separate aquarium is another. Selecting the proper tank mates will also help avoid problems. We always suggest providing hiding spots (discussed more later) so that fish have a place they can retreat to, no matter what is making them nervous.

Tank Overcrowding

We know how much fun it can be to keep tropical fish, but it can lead to too many fish in the tank if you are not careful. If you find yourself always adding new guests to the aquarium and notice your angelfish hiding behind plants or equipment, it might be time to remove some fish (which is always a great excuse to start a new aquarium setup).

Overcrowding can lead to poor water quality, fish bullying, a lack of hiding spots, and aggressive competition for food and other resources.

All of these can lead to sickness and other manifestations of stress, including abnormal hiding. Keeping an acceptable number of fish in your aquarium will help promote more open swimming, which is ideal with an angelfish’s unique appearance.

Use at least a 20-gallon tank for a single angelfish or 30 gallons for a pair as a minimum tank size. Add ten gallons per freshwater angelfish. We wholly agree with the tried and true method of adding a gallon of water for each inch of fish beyond your angelfish if you plan to keep them in a community tank.

Poor Water Conditions

Water parameters are crucial for tropical fish, and poor water quality can explain why your fish are always hiding due to stress.

We suggest weekly checks using a water test kit to verify pH, hardness (discussed below), nitrate levels, and other parameters. Your goal should be numbers like a pH of 6.5-7.5 and a hardness of 5-12 dGH.

A critical step in maintaining aquarium water is doing a partial water change of 25% or less at least weekly. It aids in keeping nitrate levels in check and promotes a healthy nitrogen cycle.

Maintaining an adequate water temperature is also necessary to keep your angelfish content. Temperature ranges between 75 and 84 degrees Fahrenheit work well, and we often keep our tanks near 80 degrees to provide a happy medium.

Think of your aquarium water like the air that you breathe. If it is clean, adequately humidified, and at a comfortable temperature, you can take a breath with no problem.

Conversely, polluted air that is too dry, moist, cold, or hot can make breathing more difficult. Your angelfish will become stressed just like you would if its water column is poorly maintained. It might want to hide away just like you might want to hide under your covers when you feel sick or stressed.

Hard Water

Of all the water parameters in a fish tank, water hardness often gets overlooked or is confused with pH. This indicator lets you know the mineral levels in the water.

While the Amazon River Basin tends to have soft waters due to rain runoff, many captive-bred specimens come from areas like Florida, where tap water has a higher hardness rating.

If water hardness is outside of acceptable ranges, it can increase stress levels for your freshwater angelfish. We recommend waters in the 5 to 12 dGH (degrees of general hardness). That puts aquarium water in the soft to moderately-hard range, which is acceptable to most aquarium fish.

We recommend checking your tank’s general hardness monthly at a minimum, perhaps more often in breeder tanks or aquariums with juveniles. Using a water test kit like the API GH & KH Test Kit can tell you if this is a potential problem or if there is another answer to your question why is my angelfish hiding?

Do Angelfish Need Hiding Spots?

We agree with breeders, keepers, and veterinarians who state that providing hiding spots helps to make aquarium fish feel safe.

Your angelfish is a cichlid that eats other fish, but it is hardwired to be wary of becoming potential prey. Fish bullying, hierarchical disputes, and other factors may require a place to get away to prevent the stress from overwhelming the fish and making it susceptible to illness.

Planted tanks using artificial or live plants, driftwood, rocks, caves, and other decorations can provide cover for your pets. These can also become a point for males to establish a territory around. We never keep our freshwater angelfish in bare tanks.

The Reasons Are No Longer Hiding From You

It is okay if your angelfish hides around the fish tank, but continuous hiding can signal something out of place. Common issues include illness, aggressive tankmates, fear of predation, overcrowding, and poor water quality.

You can observe the tank to determine aggressive behaviors or use the API GH & KH Test Kit or other equipment to monitor water parameters. Verify your filters and heater are working correctly, and treat sick fish. That should keep your fish tank’s inhabitants out in the open.

Leave a comment about this or other topics relating to your favorite South American cichlids so we can continue the discussion or answer any questions!


Why is my angelfish not active?

Most likely, your angelfish is not active due to a problem with the fish or the aquarium’s water parameters. Aquarium fish experience stress due to other aggressive fish or poor water quality. Your pet angelfish might also be slowing down with age, or it might be sick.

An often overlooked tank condition that can slow down activity is a lack of space, so we recommend 30 gallons for a pair of fish and an additional 10 gallons per angelfish after that. Your pets need energy from food, so there could also be a problem with nutrition. Malfunctioning equipment, water chemistry out of the norm, and high nitrate levels can also cause your fish to be less active.

Why is my angelfish not eating and hiding?

Your angelfish may not be eating and is hiding because it is sick, poor water conditions, fish bullying, deficient diet, or territorial disputes. One of the signs of a sick fish is inappetence, a lack or loss of appetite. Environmental factors can also reduce hunger; inspecting your equipment and using a water test kit can verify or eliminate water column problems.

Your freshwater angelfish are omnivores, so feed them a balanced diet providing all of the micronutrients needed to stay healthy. Sometimes, territorial disputes push an angelfish from its home, causing it stress and perhaps to hide, not eat, or both. Other times, overaggressive tank mates and larger fish will become a source of stress that forces your pet to hide or shy away from food.

Is it normal for angelfish to hide all the time?

While some hiding is normal for all fish, it is not normal for your angelfish to continuously hide. Freshwater angelfish will use roots, fallen timber, and vegetation to hide in their natural South American waters. They do this to hide from predators and to ambush prey.

Aquarium fish that constantly hide may indicate something wrong in their environment. Aquarium water that is off chemically or dirty can stress the fish, causing them to hide. You will find that aggressive tank mates and overcrowding can force your angelfish into hiding behind decor or within plants.

Why is my angelfish lying at the bottom of the tank?

In our experience, it appears that water conditions, stress, sickness, and age will cause some angelfish to lie at the bottom of their tanks. Oxygen levels, extreme water temperature, water hardness, pH, and nitrate levels can cause your angelfish to become lethargic. Stress from aggressive fish and overcrowding may force your fish to hover along the bottom of your aquarium.

If your fish falls ill with ick or swim bladder disease, it might struggle to stay in the mid and upper levels of the water column. Finally, we have observed older angelfish resting for short periods at the bottom of the fish tank as they lack the stamina to swim continuously or is dying from old age.

**Resource Links**