Brown Bugs In Aquarium

Tiny Brown Bugs In Aquarium?


Tiny brown bugs appearing in your aquarium could be one of several different creatures, including copepods, water fleas, water mites, or possibly tiny snails if they cling to the glass or the base of the tank. Many small bugs are harmless, but you might still want to identify and get rid of them.

You might be amazed to find creatures in your aquarium that you have not deliberately added, but this is a surprisingly common occurrence, and it can be challenging to identify the creature when this happens. A lot of little creatures look similar when operating on this scale, which makes it difficult to determine what you are dealing with.

Tiny Brown Bugs In The Aquarium?

Tiny brown bugs in your aquarium may be a worrying thing to see. Many people find that these bugs seem to appear in their aquariums overnight, and that they have an infestation on their hands before they know it. Many tiny bugs can breed fast and will spread through an aquarium within a few days if the conditions are good.

There are quite a few different things that you might have in your tank, but copepods, water mites, and water fleas are probably the commonest invaders. Tiny snails may look like bugs, but if you inspect one closely, you should be able to tell that they are snails, rather than insects. They will cling to the tank walls, rather than swimming freely.

If you have tiny bugs in your aquarium, take some time to observe them and look at how they behave to help yourself identify what they are.

How Do I Get Rid Of Tiny Bugs In My Aquarium?

You will need to determine what kinds of bugs you are dealing with before you can get rid of them, and how you need to treat them will depend on the other tank inhabitants and the conditions you have set up.

Once you have identified the bug, you can work on ways to get rid of it. For example, if you have water fleas, you may wish to wait a little while to see if your fish take care of the problem – many fish will predate these fleas and can kill off a colony with surprising speed.

You can increase the chances of your fish eating the fleas by reducing how often you feed them, so they are encouraged to look for food elsewhere. You can also add some smaller fish to your tank if none of your big ones seem interested; water fleas tend to be popular with small inhabitants.

If your fish don’t eat the fleas, try changing the tank water. The fleas will only survive if there is a high level of nutrients in the water, so if you replace it with clean water, the flea population will crash. Do this gradually so you don’t upset your fish.

You can get rid of copepods by shining a light into a corner of the aquarium and using a siphon to scoop them out as they gather in the light. This will probably not get rid of the entire population, but it is an effective and simple approach. Again, cleaning the aquarium to reduce the level of nutrients in the water will help.

Water mites can also be tackled by water changes and reduced levels of nutrients in the water, and they should soon disappear if you keep cleaning the tank regularly. They need algae and debris to survive, so a clean tank will not harbor them for long in most cases.

What Are Water Fleas In An Aquarium?

Water fleas are not fleas at all – which may relieve you if you are concerned about them jumping out of your tank or latching onto your fish or even onto you. They are a form of crustacean, also known as Daphnia, and some people deliberately add them to their tanks to provide live food to their fish.

These tiny insects do not jump at all; they swim around instead. There’s no need to worry about them leaping at you or biting you. They feed on debris and decaying matter in the water, and they are harmless to the fish and other tank inhabitants.

Water fleas can generally just be left to swim around and you don’t need to do anything about them. However, if the population starts to grow and your fish are not interested in eating them, you might want to take action to reduce their numbers and keep everything under control.

How Did Copepods Get In My Tank?

You might be baffled about how some of these little creatures get into your tank in the first place, given that an aquarium is almost a sealed environment. However, there are plenty of opportunities for them to get introduced.

The commonest means by which they enter an aquarium is through the addition of living rocks or aquarium plants. Often, these tiny insects will be clinging to the plant or rock, and when you add it to your aquarium, they are added too.

Live sand may also contain copepods, and they will soon spread throughout the tank as long as the conditions are suitable for them. They are so small that you will have almost no chance of spotting them on the material before you put it in the aquarium.

Other insects can also be introduced in this way, particularly those that are small. They will then grow in the aquarium, start breeding, and create large populations. Any time you add live plants, rocks, sand, or even fish to your aquarium, there is a chance that tiny hitchhikers will also be placed in the tank.


If you have tiny brown bugs in your aquarium, you don’t need to panic; most of these are harmless and will not bother your fish, plants, or invertebrates. They will usually be feeding on nutrients in the water, so if you want to get rid of them, changing the water and decreasing the nutrient levels are good first steps.