MH is Metal Halide which is good for growing. MV is Mercury Vapor which is bad for growning. Too much heat and not the right light spectrum.
I was meening metal vapor see i got a hps from home depot its only 70 watts i have a 3+3 room i do not thank that its strong enough to do what i need at home depot thay had metal vapor lights i dont know if it is the same as a mercury vapor it was 150 watts i read mh is the best for growing and hps is good for after thay flower or shoud i git a a secend hps 70 watts which wood give me 140 watts or keep looking for a mh and run both how many watts shoud i have i want to do about 6 plants please help need some good advice!!!!!!
I've never heard of metal vapor. Either Metal Halide or Mercury Vapor. For the size area you are speaking of and the number of plants those 70 watt pieces of crap from Home Depot are weak. You have 9 sq ft of space and you want optimally 50 watts per sq ft or 450 watts. So, for best results you should have either a 400 or 430. Get you 2 or 3 dual 4 foot flouros and some cool white and warm white tubes. This will run you between $20 and $30 bucks. Then set you up a veg chamber. Then go to Inside Sun, http://www.insidesun.com and get you a 400 watt HPS with remote ballast, hood and socket and new bulb for $80. Now you can set up your flower area. So now you would have flower area and veg area lighting for around $100. Do a SOG grow for better yield in a small place such as you have. Hope this helps! ~Worm
you mean sea of green right I do not know how to do that .i have heard of it but thats about it . i toke your advice I toke back that 70 watt light and whent to lows and got two 150 watt hps flood lamps (lots more light) I was wondering if you know if I got a mh bulb could you use the flood lights to run them or are the ballist different i can get bulbs for 15$
Do some reading on SOG. Here's a link to get you started. http://www.dopequest.com/growtips.htm There's a menu listing but the quick links aren't work so if you scroll down about 1/5 of the way you see the subject: Sea Of Green. The 150s are definitely an improvement. And, no, you cannot put a mh bulb in an hps light. The ballasts are different. ~Worm