my grow room is 181 cm long and 205 cm high, i have 400w hps which i put 4 plants under, i have enough room for another 4 but want to know should i use a UFO light or another 400 w hps. i don't no what sort of results to expect from a UFO but no heat from the light would be good for my set up. what do you think i should use am either going to buy another 400w or a UFO thanx for any replys