So my tank has always been on the warm side and I am thinking it could be from my return pump. To test this I would like to turn off my return pump and thus cutting off all filtration. I have 6 fish most of which r smaller than 4 inches. I have plenty of powerheads for circulation but how long could I go without using the filtration safely? No corals but I do have an anemone (the reason I want to get the temp down in the first place). Thx to all who respond