I took a media bag and cut it open . Glued it to some plastic and used it for a filter in my sump . The diatoms stuck to it very nicely. So I clean it every day. Diatoms are gone now but still running that filter. I would think filter bags would work you just have to clean everyday. This is for the ones that disappear at night and reappear when the lights come on. I thought I got rid of them running uv sterilizer but my bulb burnt out and they came back.