sponge filter is it working

[terrypin]

I have a small sponge filter in my main tank at the moment purely because it is spare and I have not used them before so was curious how efficient they were. I have taken it out to rinse it when I do a water change and when I squeeze the filter it is clean and I am not sure it is working .

 

[Metalhead88]

Sponge filters are very effective biological media. It will get dirty in time, but since it isn't great mechanical filtration, it won't get very dirty in a short time.

 

[terrypin]

Thanks for the reply I thought they were more mechanical no wonder it is not dirty. I will stop washing it out and give it a chance to grow some good bacteria.

 

[Metalhead88]

Well, they do provide some mechanical filtration, but nothing like filter floss would.

How often did you rinse it?

You should have a nice flow of bubbles coming back out around where the airline is connected.