A Guide to Easy Fish Tank Filters: The Sponge Filter

So you’ve already made several important decisions with respect to your fish keeping hobby - you’ve chosen your aquarium and fish; positioned the aquarium in a location that will provide maximum comfort to the fish and you’re now reaping the relaxing rewards of an at home or office aquarium. 

But are you keeping on top of the key ways in which you can keep your tank clean and your fish happy? One such way to achieve this is through the use of a sponge filter. Many aquarium owners are not aware of how a sponge filter works or sometimes even of their existence. At Aquacadabra, we’re here to share our knowledge and ensure a happy experience for both you and your fish family.

Sponge filters have actually been in existence more or less since aquarium keeping began, and although they aren't perfect for every type of tank, there are many situations in which they are a great solution to keeping your tank clean and healthy. 

What is a sponge filter?

Aquarium sponge filters are one of the most cost effective and easy to use filters. But despite their low cost they are surprisingly a very effective tool to clean the water of your aquarium. The most basic sponge filter is made up of three components: a piece of foam that sits inside the tank; an air pump that sits outside of the tank; and some airline tubing to connect them together. Sponges can come in a variety of shapes, sizes and pore sizes to suit your particular type of tank.

Bio Sponge Filter, Aquacadabra, £8.99

How does a sponge filter work?

A sponge filter will initially provide mechanical filtration - this is where the filter physically separates and removes any waste and solids. And then once it has developed and grown bacterial colonies, it will provide biological filtration also - beneficial bacteria will help to detoxify and purify the water. Although often seen as the best filter to use for beginner level, this isn’t really the case as there are many pros to using them at all fish keeping levels.

The water filter process starts with the powered sponge filter air pump creating suction to enforce the water through the sponge to remove solid waste and ammonia from the tank. As fish waste releases a lot of ammonia, it is deadly even in small quantities to both fish and plants. The biological filter, by having beneficial ammonia eat bacteria, will help to break down the ammonia into nitrite which in turn will break down the nitrite into nitrate. Ammonia is still harmful to fish, but nitrate less so, so the process as a whole offers a safe and healthy environment for your fish family.

How to set up a sponge filter

If you’re ready to purchase a sponge filter for your aquarium, you’ll want to know how to set it up. Here is the set-up process in five simple steps:

  1. Before you start, make sure you have all the necessary components of the filter that we previously mentioned - the sponge, air pump and airline tubing. You can also use an air stone, also known as an aquarium bubbler, usually made up of porous stone or limewood and which will efficiently diffuse air in the water and eliminate any noise. Diffusing large bubbles into smaller bubbles will help to oxygenate the water better, plus it looks better too!
  2. You should attach the airline to the nipple at the top of the lift tube.
  3. If using an airstone, attach the airline to the second nipple at the bottom part of the top of the lift tube. You can then plug the air stone into the airline.
  4. Next, install the check valve with the air pump on the side that the air goes through. The check valve is best placed up by the rim of the tank.
  5. Finally you can plug the filter into the air pump - just make sure that the air pump is pumping air through the sponge filter along with the water. 

How to clean a fish tank filter sponge

One of the key benefits to using a fish tank filter sponge is the easy maintenance of them. You should aim to clean the sponge filter regularly, ideally between one and four weeks. They get visually dirty, so it’s quite easy to be able to see when they need a clean. By removing some of the aquarium water into a bucket, you will be able to remove the filter and squeeze the sponge for a few minutes until you have released all of the dirt and debris. Be sure to use the existing aquarium water for this process as it will ensure the original beneficial bacteria will remain and you don’t need to start the process again to grow back the beneficial bacteria needed for biological filtration.

As you can see, learning how to use an aquarium sponge filter is a simple and effective process that isn’t going to cost you very much money. It’s a tool worth looking into if you haven’t already.

At Aquacadabra, we’re one of the original specialist online aquatic retailers and have one of the largest selections of aquarium filters and filtration equipment in the UK. Browse our full range of sponge filter products and full range of fish tank filters to help equip your aquarium for everything you need for a healthy fish tank with a happy fish family.