Hi i have 180 h 110 w 65 d and used a 400w it was to hot when lowering the light to the plants, plus it helps if you have good intake and out take fans, the humidity i had at 50% but the lighting was suspect, i have now lowered to 250 w have industrial intake and outake fans and it works fine for veg i use 250 w spectral blue and then 250w red for harvest, seems to be fine for me, you should really set it up before plants added to get it right and keep temp steady.