I went away this weekend and I when I returned, the water looked very cloudy. From a distance, there appeared to be many little air bubbles in the water. When I took a much closer look, there are thousands of tiny, 1-2mm, white creatures swimming in the water and crawling on the glass. Does anyone know what these are and how I can get rid of them. I would post a pic, but they are way to small to show up in the pic