Filo,Filo said:I dont know what is making it turn green...i did a couple water changes last week to try and eliminate the problem. 70% water change--made is nice for the day--then turned green hue after, 25% water change, same thing. I dont have a phosphate test kit tho. Someone told me to just cover the entire tank with black garbage bags so NO light touches the water. Wouldnt that be bad for the fish?