I get commissions for purchases made through links in this post. Learn more.

Sponge Filter vs Power Filter (HOB Filter)

What is it that you consider when you plan to keep pet fishes?

Well, surely the first thing is a nice aquarium. Also, you perhaps think about plant life and substrate and feel you are done.

But, do you know to keep the water in your tank clean and healthy you also need a filter? A filter has a very important role to play in any fish tank and we shall learn about the same in brief right away.

[amazon table=”8842″]

Why Do You Need A Filter?

Filtration is necessary to move and clean the aquarium water and thus make it safe for your fishes. The three types of filtration are mechanical, biological, and chemical.


Mechanical Filtration makes use of filter socks, filter floss pads, and sponges to eliminate debris from tank water. It quite behaves like a garbage can that collects trash that you have to empty later on. You have to remember to empty the trash, or else, there are chances of it overflowing.

However, mechanical filtration alone is not enough as it does not convert nor remove ammonia, nitrite, or nitrate present in the tank water. It removes the free-floating wastes prior to it converting into harmful substances. If you want the filter to serve its purpose you have to clean or replace it once in 2-4 weeks. Mechanical filtration even helps in aerating the tank water.


Biological Filtration makes use of beneficial bacteria to consume harmful nitrogen and ammonia compounds. Such helpful bacteria need oxygen-rich water and a good surface area like sand or rocks to grow on. This is why many filters include bio rings or bio-media with a big surface area for these beneficial bacteria to thrive.

It is very important for every aquarium to have biological filtration. If you have just a few fishes in your tank, chances are, biological filtration alone can be enough. However, in other tanks, the other types of filtration are also necessary.


Chemical Filtration makes use of special resins or activated charcoal to remove tannins, medications and any other impurities from the tank water. After the chemical filtration is soaked with impurities, the media can no further absorb pollutants present in the water.

Basically, mechanical filtration make the water clearer. biological filtration helps make the water safer and  Chemical filtration is what helps eliminate impurities from your aquarium water.

So, filtration is indeed very important and for the purpose, you need the right filter. Among the most commonly used filters are the sponge filter and power filter. We shall learn about both of these in detail through a sponge filter vs power filter (hob filter) comparison.

What is a Sponge Filter?

[amazon box=”B0051XIN78″]

A sponge filter basically has a sponge through which your tank water will be drawn. It offers mechanical filtration. Once the sponge matures and bacterial colonies grow on it, it even offers biological filtration.

You can get the sponges in different sizes and shapes. You even have the option to select your preferred pore size. It is possible to power them through various methods. This includes powerheads, air pumps, and also another kind of filter.

Sponge filters are amazing when you need gentle and safe filtration. For instance, you can use it in your fry tank where standard filters might suck the little fishes. Fishes like betas that cannot bear strong currents also will survive well if you choose a sponge filter.

Pros and Cons of Sponge Filters


  • Sponge filters are easy to clean.
  • These filters are hard to break because they do not have many mechanical parts.
  • They offer good surface agitation and water circulation.
  • They are quite gentle and thus a great choice for little, delicate fishes.


  • They are not aesthetically attractive.
  • There is no chemical filtration at all.
  • Needs a (air)-pump to work

Check Price and Reviews on Amazon

What is a Power Filter?

[amazon box=”B0007ZS230″]

A power filter, also known as hang on back (HOB) filter is a kind of filtration that clings on the back of a fish tank. This type of filter has become quite common nowadays. A motor, in this case, pulls up the tank water through the filter. Then, it trickles back into the tank.

This kind of filter offers mechanical, biological, as well as chemical filtration. You can combine them with a bio-wheel and enjoy even better biological filtration. Almost any standard tank can use HOBs. They filter the tank pretty well and offer necessary surface tension.

Power filters are easy to install and easy to maintain. Since it hangs on the back, you do not even need to worry about finding any extra space to install them.

Pros and Cons of Power Filters


  • They offer mechanical filtration, biological, and also chemical filtration
  • They are easy to use and easy to maintain.
  • They offer good surface tension and clears water pretty well.
  • As they hang on the back you do not have to find any extra space for installation.


  • Some power filters may produce a little noise.
  • The filter cartridges can be expensive.

Check Price and Reviews on Amazon

Sponge Filter vs Power Filter (HOB Filter)

Now that we are aware of what a sponge filter and power filter is let us draw a comparison and learn about what they share in common and how are they different.

What they share in common?

  • Both sponge filter and power filter offers mechanical as well as biological filtration.
  • Both of them filter the tank water efficiently.
  • Both of them are easy to use.

How are they different?

  • Power filter offers chemical filtration, something that sponge filter does not.
  • Sponge filters are placed inside a tank whereas a power filter is hung outside.

[amazon table=”8842″]


Filtration is immensely important no matter what your tank size or what type of fishes you choose. Without proper filtration, the tank water will be unhealthy and your fishes may even eventually die. So, a filter is something you just cannot do without.

As far as selecting the best filter is concerned, both the sponge filter and power filter make a good choice. Now that you have gone through the sponge filter vs power filter (hob filter) comparison you can decide which one will make a better choice. Just consider your needs, the kind of fishes you have, and you easily will be able to decide which one to opt for.

Topic Related Article

Sponge Filter VS Canister Filter

Aaron Boyd
Aaron Boyd

Hello, I’m Aaron Boyd, the proud owner and author behind Aqua Movement. I hope my article was able to answer your questions. If you want to learn more about me, click the home icon above.

Aqua Movement