from the blog

Unusual Behaviors in Aquarium Fish

Caring for fish

September 30, 2020

Cultivating a home aquarium is an exciting challenge. Not only do you get to build and maintain a thriving aquatic environment right in your own home, but you also get to experience the joy of watching your fish thrive and grow. Aquarium fish can be extremely entertaining to watch because they display a variety of amusing behaviors. Some fish develop dog-like personalities while others put on impressive displays in order to attract a mate. There are some behaviors, however, that are downright strange or confusing. Read more to learn what some of these behaviors are and what you can do about them, if anything.

Croaking and Chirping

Certain species of fish are capable of making croaking or chirping sounds. These sounds are produced by vibrating a set of muscles against the swim bladder of the fish. While it is unknown exactly why certain species produce these noises, it is believed to be related to mating or aggression. This behavior is completely natural so you do not need to worry about it.

Blowing Bubbles

Gouramis bubble nest

If your fish begins to blow bubbles at the surface of your tank, it could be building a bubble nest. Certain species of egg-laying fish build nests for their eggs out of bubbles of air and saliva – some of these species include betta fish and gouramis. It is typically the male of the species that builds the bubble nest and, after spawning, collects the eggs and transfers them to the nest for safe keeping.

Rearranging Tank Objects

This type of behavior is most commonly seen in large cichlids, particularly Oscars. Generally, these fish exhibit this type of behavior because they are searching for food in the substrate. Because cichlids tend to do this, it is best to avoid using too many decorations in the tank and to only use those that do not have sharp edges so your fish doesn’t injure itself.

Fin Nipping

Some species of fish tend to exhibit this behavior, nipping at the fins of other fish in the tank. Some of the most likely culprits for this behavior include tetras (particularly serpae tetras) and some species of barb. Fin-nipping fish tend to target species with long or flowing fins so it is best to avoid keeping fin nippers away from long-finned species such as angelfish and betta fish.

Darting Around the Tank

It is not necessarily a bad thing if you see your fish darting around the tank – some species simply move more quickly than others. If this type of behavior is not normal for your fish, however, it could be an indication that something is wrong with the water quality in the tank, causing the fish to become stressed. Some bottom-feeders (such as corydoras) dart to the tank surface to take gulps of air and this behavior is nothing to worry about.

The key to identifying unusual behaviors in your fish is to spend enough time observing them to know what behaviors are normal and what behaviors are not. Spending just a few minutes each day observing your fish will help you get a feel for their “normal” behavior so you can quickly spot changes. Sudden changes in behavior may be an indication of illness, so you should do everything you can to keep your tank environment clean and healthy to prevent your fish from falling ill. One easy way to do that is to install an EcoBio-Stone in your tank. EcoBio-Block Products are infused with live beneficial bacteria colonies as well as the nutrients they need to multiply and maintain the nitrogen cycle in your tank. Once the nitrogen cycle has been established, the beneficial bacteria will work with your aquarium filter to help keep your tank water clean and healthy for your fish.