I have an Aqueon "Quiet Flow 10" as a HOB filter on my 10 gallon tank. I have had it running for several months now. When I opened it up today, I was not very satisfied with the filter's standard "bio-Holster". It hardly had any bacterial growth on it! I wanted to get the most out of the biological filtration so i decided to to something about it. I basically replaced the plastic "bio-holster" with a piece of sponge. Here is how I did it if anyone is interested.
What you will need:
Here is the filter's "bio-filter" as you can see it hardly has anything in it, I was not impressed.
Here is the kind of sponge I used. I got it at petco for $2. I wanted to use someting I was certain is aquarium safe.
I then cut the sponge in half lengthwise. So I ended up with 2 strips of sponge each of them (pprox 3.5 inches long and 1.5 inches high). Here is one of them:
I then cut off one of the corners, that way the sponge will let the filter lid fit tightly.
I then squeezed the sponge and stuck it in the filter as shown. In the pic you can see that I already have another sponge installed. The reason I squeezed it in there (and not cut off the excess) is that I wanted to get the most surface area for the bacteria to live in. And also because it will prevent it from falling out.
The sponge I have is yellowish-brown because I used the sponge I baffled my filter with and it was already loaded with the beneficial bacteria. This method also cut down the current in the tank to the point that I feel that I no longer need to baffle my filter.