Hey guys, I keep getting algae on the top of my rockwool cubes. Thankfully, I live in a place where i can buy clones at the store, and within a week, about a third of them get a film of either green or black goo on the top. The rest are clean. I keep the humidity at 50%, use gh 3 part, floralicious plus, and root juice. I tried flushing them more often, didn't matter. Other growers say they all get it too and it doesn't hurt the plants but those clones always seem to be lagging behind. Oh, I tried scraping it off but it comes back fast.