I don't know anything about diatom filters. I read somewhere that you could use a magnum 350 filter and use the micro filter with diatom powder. I have a magnum 350 (currently not using on my tank) and wasn't sure how to use the powder. Do I sprinkle it on the micro filter? I didn't know how to go about it? I wanted to make my water crystal clear and it has been very cloudy lately. Thanks