I have a 10x10 ft room, 8 feet high. I have 2 1000whps 4 feeyt inwards from walls in centered line, one 600 MH inbetween the 1000w's and at a foot below them. I have a 3 level stadium, not collisium, a stadium, looks like football stadium ya know. bleachers on all four sides with a 1-2ft gap to enter the center. I got with this setup, my first time, 3.4 LBS and that was with PH mistakes, nutrient over/under/ lockout not sure all I know is I was asking a million Q's at growq store and they never had to help same q's twice. so I fixed problems quick as possible. Also this is my 3rd run, summer sucked only 2.5LBS because i DIDN'T USE AN a/C i JUST IMTERMITTENT my lights andf lost alot of the wieght with such hot air intake and room. This time I have H&G everything, drip clean has fixed a problem occuring with my soil PH going catty wompus. I am into week 6 today, so shooting powder, week 1 I added bud bloood, 2-end of week 4 big bud, and week 5 was H&G top boooster and bud xl for 3 days. then just bud xl caries on into shooting powder. also I will be using roots exculerator in shooting powder. Anyways Onto UVB. I have 4 cfl 26w 10.0vb reptile bulbs. One is in each corner set in twards center of room a bit and each one is showering top buds on tope and middle shelf excellently, sure some makes it about a foot lower to bottom shelf top buds. I do have a 5th uvb cfl in a lamp in center of floor to subject lower plants with it too, but that one is kinds be hitting from bottom up[ on the lower plants. still ok tjhough. Well to say ytou cant see a difference is wrong. I see huge differences. my uvb's start when plants are rooting into the final pots in flower room before switching to flower when still small. You don't want to overdo it, I start at 1-2 min intervals, my timer is 7 time cycles a day, runs the same program day in and day out. I workj my way up to 12-20 mins. So my lights come on at 7pm and go off at 7am. ( I work up adding a minute to each uvb cycle every 4 days or so about week 3-4 I am at full)at 10pm uvb lights at full amount are on 12 mins, then 11pm they go for 15mins, 12am is 17 mins, and the plants solar noon is actually 1am because light cycle is 7-7, at 1am they on for 20mins. then it goes back down the same way, to effect them like nature, as best as we can. I researched alot before I started. You Do not want to leave them on continuously, UVB on the equator is only as powerful as a reptile bulb at noon, besides the point is to try and burn, hurt them, then they heal crystalize ect. Seems much more crystal covered. I have one starain starts with purple in buds, ended with purple in buds, Nowe with UVB at halfway the coating of crystal has rid of any visible purple, and yeah, I plan on using uvb always. And I would reccomand the 10.0 uvb and hang them vert. don't put them closer than 8 inches as the heat could stress the plants. hot heat emitting the reptile bulbs. Cheers Go House and Garden, easiest nutes to use, PH, and the results are the best, but to be fair I added bud blood, big bud into thier egime, now shooting powder HEHE Fucking Eh!