A lot of people do not know about a freshwater sponges aquarium or are confused about how to use them. If you are in the same boat, don’t miss the lines below.

These organisms normally appear in saltwater. However, this writing provides a comprehensive review of the freshwater species. They can live well in your home tank and benefit the marine inhabitants.

What Are Freshwater Sponges?


Most sponges are known to live in salt water, and only one family of them grows in freshwater, which is called the genus Spongilla.

Freshwater Sponges

What do freshwater sponges look like? Unlike its relatives, Spongilla appears simply gray, brown, or green when algae are sticking to it. The freshwater family comprises 150 species in total.

There are six out of them reside in the lakes, rivers, and ponds of Illinois, as well as slow-flowing or standing water. Although Spongilla can reach a width of one meter, its height rarely gets more than 15 centimeters.

Based on scientific estimation, approximately 75 species can survive in a new habitat that is different from their original life.


As mentioned before, people can find freshwater sponges in lakes, rivers, streams, and ponds. They grow on the surface of submerged solids. Thanks to being sensitive to the living environment, these species can indicate excellent water quality and negligible pollution levels.

Sponges are categorized as filter feeders. It means particles and tiny organisms existing in the tank are their food, filtered by circulating water through their body structure. Besides, these creatures also get nutrients from the sticking symbiotic algae.

Meanwhile, freshwater sponges are used to feed crayfish, ducks, and numerous macro-invertebrates.

[display-posts id=”2057″ image_size=”thumbnail” posts_per_page=”1″]


Freshwater sponges are motionless organisms residing at water bodies’ bottoms. Despite having no backbone and organs, these species possess specialized cells to filter the food in water flows. They crave bacterioplankton, organic particles, and the nutrients the symbiotic algae produce.

Amateurs may mistake the green algae for the freshwater sponges. However, they are different in texture and thickness. Sponges’ texture is coarse and thicker compared to the algae living on them.

Once minor pieces are broken, these organisms can reproduce either asexually or sexually as a replacement. The same goes for the broken parts after forming gemmules, which are overwintered reproductive spheres creating newborns.

Scientists analyze the structure of gemmules through a microscope to categorize the species levels.

Freshwater Sponges Aquarium Review – Are Sponges Safe For Aquariums?

Freshwater sponges take responsibility for filtering the particles from their aquarium environment. The water flows through their cell walls, which draws dissolved organic elements.

This process produces a nutritious solution and converts the bacteria into energy to absorb. This energy helps them develop and survive in a low-nutrient environment.

Sponges are beneficial for your tank as they consume small organisms and algae. Having these organisms in aquariums gives things like crustaceans and corals more space to develop at the bottom of the tank.

Moreover, these aquarium filters can provide housing for tiny fish and creatures.

The shape of this motionless organism varies depending on your tank’s temperature, water clarity, and light settings. For instance, they may appear creeping, prostrate, or have structures of upright branching.

[display-posts id=”1934″ image_size=”thumbnail” posts_per_page=”1″]

Drawbacks And Benefits Of Aquarium Sponge Filter


  1. These organisms are economical to purchase. Specifically, most of them cost at least twice less than corals. Thus, freshwater sponges are the best bets for buyers with limited budgets or amateurs starting to build diverse and spectacular aquarium habitats at home. You can easily find this product in the local fish stores. Besides, online shopping is another option with no movement required and better choices offered.
  1. These living filters require little effort for maintenance and management. A proper condition for their development is only efficient lighting and some other specialized equipment. That’s why it is easy for beginners to handle their tanks.
  2. Freshwater sponge species are either the accommodation or food for the fish in your aquarium. Some aquarists even serve their fish only with this food.
  3. You can move or arrange these motionless organisms effortlessly as they are small in size and lightweight. Furthermore, they nestle at the bottom and are just a few inches high. Thus, you can keep them intact while moving.
  4. Other aquatic plants tend to put down roots around this kind of organism. Thus, it paves the way to green your aquarium easier.

[display-posts id=”2597″ image_size=”thumbnail” posts_per_page=”1″]


  1. Some species of freshwater sponges are harmful to aquatic animals like shrimps. However, the chance for this issue to happen is rare. It can be approved that most species are safe for fish and other inhabitants in your tank. If you still worry about this problem, ask for advice from an expert before purchasing.
  1. Some varieties may spread too fast, which leads to a decrease in the aquarium’s oxygen levels. You’d better separate them into solitary specimens or place them at the back of your tank.


How To Maintain Sponge Filter?

It is not challenging to preserve a proper sponge filter, even if you are a beginner. The technique is simple, as long as you regularly perform this process. First and foremost is changing water.

Remember to save an amount of the old water, which is enough for you to submerge the sponge. Keep gently squeezing and releasing the filter until the collected particles are dislodged.

In addition, when it comes to numerous species in your tank, try not to separate their cleaning schedules. Thanks to that, the maintenance poses a smaller effect on the aquatic colonies and the biological balance.

[display-posts id=”2368″ image_size=”thumbnail” posts_per_page=”1″]

Can I Use Sponge Filters For A New Aquarium?

Definitely yes. You can place the filters once your tank setup is finished. They will maintain the biologicals and even boost the aquarium environment by decreasing nitrite spikes and ammonia. Don’t worry, as you can even rearrange these organisms freely later.


Although it is easy to purchase a freshwater sponges aquarium, keeping the habitat balanced and the creatures in it healthy is not a simple task.

Follow the tips and maintenance methods mentioned above to have proper care of your filters. With ideal preservation, they will make your tank look spectacular every time.

Alex is a pet freelance writer and editor with more than 10 years of experience. He attended Colorado State University, where he earned a Bachelor’s degree in Biology, which was where he first got some experience in animal nutrition. After graduating from University, Alex began sharing his knowledge as a freelance writer specializing in pets.

Comments are closed.