Easy Question for Master growers like you:)

do you think 3 x 150w hps lights will work fine with 6 plants hydro grown? in a 2' x 3' system length in a 4'x 6' room?

Not as well as a single 400.

as long as the light is contained and the lights are close. I hope you have a good set up.

i have an amazing set up for the hydro system. diy way though i will post a grow journal so all you can see. i used 4 x 150 wt hps for 3 soil grown plants and got just about a qaurter pound off them. so i feel confident. but i want to take one of the hps lights and do 1 plant soil(cole train) i like to grow so i want to try many methods. btw the six plants are lemon skunk. but why would you say that 1x400 would be better than 3x 150 because 1 its 50 watts more, i under stand the lumen output is different though i can accommodate that due to me being able to put the lights closer. which i can put them about 6 inches away at points though i am gonna play it safe and keep it around a foot away.

you could put 1 site under each 150watt and pull nicely for sure. with 2 sites under each bulb your allocatting 75 watts per site which is still technically ideal, but real world results- yer a little short on lighting imo, but that depends on what kind of yield your expecting. also i dissagree that 1 400 watt is superior to three 150's, i'd take the three 150's and spread that light better, but to each his own. i really think you could do best by cutting numbers and run 2-3 larger girls under the three 150's so you have a central light plus 2 on the sides and a fully illuminated canopy(maybe even some t5's down low. if you ran six- you should def add some low laying supplemental light).me... i'd run two fat girls LST style(how is your training game lol?). i think your yield would be superior to the six site set up. but the set up you describe would be fine.

I think why he's suggesting 1 400w is because of penetration. The total wattage might be similar, but the stronger single light will penetrate much deeper, even through leaves. Works the same way with flo's too, the more area they cover (the further apart the bulbs are), the less penetration you get. I've been running MH's over aquariums for years, and if you take a par meter you will find the values much higher in deep water with a 400w than you will with 2 250w's.