Ok first off why does every body thing lighting has to do with growth in a big way . Well it doesnt light has very little to do with growth . Lighting is just for the sps zooxanthellae that live in the coral tissues and gives them much of there color. Zooxanthellea which intakes carbon dioxide and produce oxygen and carbohydrated for the corals. This is what good lighting does for sps. Growth now is throw stable alk, cal, and mag at NSW levels . Thats alk from 6.5 to 8.0 DKH Cal from 320-400 and Mag 1200-1300. Sps in with wild reef get no light sometimes for a good mounth and have good Growth without the lack of lighing . Acropora are able to grow 10inch a year under these conditions. And yes salinity and temp also play a roll in this . To do this is not hard to do at all . My alk stay alk stays at 8dkh and doesnt move at all same with cal 380 all the time .