Hi, new to the forum and about a year into fish keeping. I have two tanks. One 20 gallon that has been going for about a year now and a 2 month old 75 Gallon. I thought I had a micro bubbles issue in the 20 gallon. In the 75 gallon the water appears the same. Here is the picture: The picture is about 15 minutes after turning the canister filter off. The bubbles like structures seem to join to form longer strains when the water is still. They don't float to the top, just stay suspended. With the filter moving the water they appear to be consistently dispersed throughout the tank. The water in both tanks is fine. 0,0,30. The tanks have different filters and substrate. The Tetras in the 75 moved from the 20 and don't seemed to be bothered. This morning I tried my city water in a glass and it doesn't appear to have the same look. Can anyone help me out?