i use liquid light or should i say i used liquid light you have to raise the canopy a couple of feet cause if you dont your plants will burn right up i mean its really tricky to get the right amount and move the lights the right heighth.its like if you use a 400 hps your yeild would be like your using a 600wt if your using a 600wt its like 1000 ext.. so ,try it out, imean hey if we never try new things how are we ever going to get anywhere