First post on here looking for some advice. I recently built a scrubber from black acrylic, 6 x 4 screen lit by a diy led unit on each side, these have 6 x cree xp-e photo red, 1 xp-e2 blue and 1 x semiled uv 415nm. It's been running about 4 weeks now but I'm getting very little growth especially in the central area where the blue and uvs are, the lights are abiut 2.5 inches from the screen and lit for 12 hours on/off. I'm wondering if i should lose the blues and uvs or leave it a while longer....i have gently scraped the screen a couple of times and there is a bit of green growth around the edges Tank is 50 gallons 1 cube per day and i do have a bit of green nuisance algae on some of the rocks....not hair algae more like the fuzzy green stuff and wiry stuff....any advice welcome...pics will follow. Regards from U.K.