Months ago, my 40 (38?) gallon aquarium got cloudy - very cloudy like I've never seen before. I don't know if this was a mistake or not but I bought a product that was suppose to clear it. Shortly after I added that, algae grew like (you guessed it) I've never seen before. I tried leaving the LEDs off for days. I tried salt. I tried water changes but I couldn't beat the algae. The water looked like pea soup. Finally, some combination beat the algae and the water cleared. I was just sitting and looking at fish that I haven't seen for months. It appears the algae did not bother them. I could find every fish I can remember having when it went green.