I just put two L.E.D. lights over my 72 gal. tank. Total both lights put out 6680 lumens. I don't know how to convert that into watts. Hoping they put out at least six watts per gal. as I would like to keep most types of coral.
What LED's did you buy? The marineland "reef ready" lighting is by the way not sufficient for a reef. LOL Not sure how they can get away with saying it's for a reef as you can only keep basic corals with it.
Alot depends on the actual fixture and watts of the little led's.