It was pretty clear yesterday, then I vacuumed. It kicked up some debris and made it cloudy. I assume that debris is what ate the chlorine? My cheapo test said I was at 4ppm before I vacuumed, now this morning PAP says I am at 0 again. Right now its still cloudy from the vacuuming. I changed the cartridge to a clean one after the vacuum and let it run all night. Still cloudy though.