[freemike]

I'm so confused on what the filter is right now have read so much material. My filter (http://www.walmart.com/ip/Tetra-Whi...-Gallon-Acquariums-Power-Filter-1-ct/10291764) has a white cartridge and black plastic spongy material in it. So how do I maintain it? I really don't want to upset my cycle by changing something I'm not supposed to change.

 

[freemike]

The reason I ask is because one of the white filter cartridges on identical setup looks a lot dingier than the other and the water isn't being cleaned nearly as effectively in that tank. The tanks are going on two weeks of use granted on the one that has the dingy filter I did not rinse the gravel properly so maybe I have used up that filter use with cleaning the particles that were stirred up when water was initially added. Also is the white part the chemical filter and the black filter the biological?