I’ve heard of a few horror stories of UVB lights from growmua5 and medgrower. Something about stressed plants, seed pockets and lower yields. Not sure it’s worth the added expense.
I went with a far red led board instead by rapid led & growmau5.
They come on 3 hours before my lights shut off and go off 15 minutes after they shut off. Suppose to help simulate the Emerson effect.
That coupled with a 11/13 light schedule shaved a good week off an 8-9 week strain.
I could take em down sooner but I’d rather wait a little longer. Without the far red led board I’ve let them go almost 9 weeks for the same results.
They really could have came down after week 6 if I was rushing it. Sadly I haven’t been able to smoke for a few months so i’m letting them go.