Diy filter

[joeyjoelyjoepro]

Hi everyone, you guys have probably got a lot of questions about filters but, what if I used some PVC about 3' diameter vertical above my fish tank and about an inch from the top them, I stuff a sponge in for mechanical filtration and below that I put lava rock for the bio filtration and to hold it in I would just put something like an old screen taken out from my window (I need to replace it anyway) and put it on the bottom. To power it all could I just use a power head connected to a hose or PVC directed to the top of the filter then let gravity so the work from there?

Thanks