How To Get Rid Of Water Fleas In An Aquarium

Last Updated on January 20, 2022 by admins

Water fleas are small crustaceans that can be found in many aquatic habitats around the world. However, what to do when you find water fleas in an aquarium?

Have you ever seen any small creatures on the surface of the water? However, do you know what that is? Water fleas are a genus of small crabs that you can often find in your aquariums. Although they do not pose a danger to humans or domestic animals, they often have an impact on aquatic life.

Did you know that female water fleas don’t need males to reproduce? Or, that they have a light-sensing organ called the ocellus? Well, keep reading to find out more water flea facts.

Appearance and Characteristics

Water fleas are small, planktonic crustaceans named after their swimming style. They belong to the order Anomopoda (class Branchiopoda). It’s an extremely large group containing about 450 species that are distributed around the world. The water flea is microscopic in size. Which means it’s only about 0.2 to 3.0 millimeters (0.01 to 0.12 inches) long.

They live in a variety of aquatic environments, from acidic swamps to freshwater lakes, ponds, streams, and rivers. Some of them even in rain-filled tire ruts or several meters from the ground, growing in tree moss in a rainforest. Although there are several marine species, water fleas can generally be considered freshwater organisms. They live in water columns in which they remain suspended by using their legs and antennae for movement.

We can most often notice them in the upper part of the water column, near the surface of the nutrient-rich water. However, depending on the season or predators, they often move on other parts of the water column as well. These animals form a component of ‘zooplankton’ which consists of a group of small/microscopic animals that act as primary consumers in aquatic ecosystems.

So, you are wondering what eats water fleas? They are the prey of tadpoles, salamanders, newts, aquatic insects, and many types of small fish.

Appearance and Characteristics

Learn more about: White Haze On Aquarium Glass

What Is The Most Common Type Of Water Flea In Your Aquarium?

Daphnia Pulex is the most common species of the water flea. The name water flea comes from the close resemblance to that of the terrestrial flea. That is to say, similarity in body structure, and movement through water, a jerky, hopping motion. They live as plankton in the open water of lakes or attached to vegetation. We even find them near the bottom of the body of water. Furthermore, its body is very small and weak to live in a strong current. That’s why Daphnia lives in freshwater.

When it comes to feeding, it spends most of its time creeping along the bottom of a pond or lake, looking for food particles. It’s considered one of the most common foreign inhabitants in your aquariums.


Did you know that there are many more females than there are male fleas? Do you know why? Females are able to incubate unfertilized eggs inside their bodies. In short, they can make clones of themselves.

However, as always, there are exceptions. When there is a lack of food or it gets very cold they produce eggs that are fertilized by the male sperm. Consequently, this results in offspring with broader genetic variations. Very convenient from an evolutionary point of view, right?

Are Water Fleas Bad For My Aquarium?

The good news is, water fleas will not cause any real harm to your aquarium. However, before you allow them a carefree coexistence, first check the following:

  • Will water fleas injure or disturb your fish and other aquarium animals?
  • Is there a chance that their presence will contaminate or reduce water quality?
  • Will water fleas affect the aesthetic quality of your aquarium?

How To Get Rid Of Water Fleas In A Fish Tank

Another positive thing about water fleas in aquariums is that they’re nutritious live fish food. For instance, many owners opt for the purchase or cultivation of water fleas for this very reason. On the other hand, it’s perfectly fine if you consider water fleas to be unwelcome guests in your aquarium. These are your options.

Let your Fish Do The Work

This is one of the oldest methods of solving this problem. To persuade them, skip feeding. Consequently, they will realize how much food supplies were floating under their noses. Water fleas are usually very tasty which is why smaller fish love them. If you don’t see progress, try one of the following proactive methods.

Change Your Tank Water

Water fleas in an aquarium mean only one thing, an abundance of food and reproduction. Therefore, consider changing the water in the aquarium. This will eliminate potential food sources and reduce their repopulation.

Remember, changing the water is a sudden exposure of your fish to stress. Unfortunately, this can be fatal. Be sure to follow the standard recommendations for a safe water change.

Use A Biological Aquarium Cleaning Product

Biological aquarium cleaners reduce organic waste by effectively cleaning interior surfaces. To protect the inhabitants of the aquarium you want to keep in it, carefully follow the instructions on the label.

The Trick With Blanched Zucchini

It’s very simple! Blanch the zucchini, cut it into pieces and insert it into the aquarium. The water fleas should be attracted to the zucchini, and they’ll attach themselves to it. For better results, you can leave the zucchini in the tank overnight. And voilà that’s it!

In Conclusion

These small planktonic crustaceans are frequent inhabitants of aquariums around the world. As scary as it may seem, you don’t have to worry. These small planktonic crustaceans are frequent inhabitants of aquariums around the world. As scary as it may seem, you don’t have to worry. They’re not harmful to you or your aquarium. We hope our tips and tricks for dealing with water fleas in your aquarium have helped you. Do you have a new idea or better yet your own advice? Write to us below!

You may also be interested in an article on How to get rid of blue-green algae in a planted aquarium as well.

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