I don't know it seemed like I was trucking along just fine under my T5s, bought the leds and everything came to a standstill. The plants look healthy rich deep dark green colors, just don't seem to be growing real fast. Hopefully over the course of the next several days I'll be able to get these lights at the optimal distance. Time doesn't bother me, for instance if I had a 60 day auto take 90 days I'm ok with that, I just want to be certain that growing under led instead of T5s isn't going to hurt my overall final yield.