Therrion
Well-Known Member
My hydroponics nutrient solution will develop this white film after about a week. it's not usually an issue, because I change the water once a week, but sometimes I'll change every two weeks if its small vegging plants. I use rockwool, the full GH flora series, and recharge. My plants exhibit no issues and I see no white spots in the medium or on the leaves. What is this and how do i get rid of it except the obvious changing of water. 
