Has anyone flowered with 100w HPS light bulbs? How many do you need to equal the output of 400w HPS with Ballast?
I have not flowered with a 100hps so I don't know the outcome.. but I'm pretty sure that you'll need about 4 100w to make 400w of output...
I read somewhere that you won't get the same results with 4x100W than what you would with 1X400w. I have looked everyewhere for a ballast and reflector and they just don't sell them here.
your probly gonna have to look for a 150 hps.. and even if you find one it'll probly be an attatched ballast security light or something.. I'm not sure companies make grow lights that small as they really wouldn't be very useful for growing... And ya you may get a little more light out of 4 100 watt bulbs than a 400 but that would just be kinda rediculous to have 4 lights and ballasts just to get a little more output.. you should get a 400 you'll be much happier with the results....
The problem is that I can't find a ballast here (PTY); the closest thing I found are floodlights that have the ballast already incorporated into one part, its a metal box that weighs about 40 pounds and has a very small reflector and its expensive. I was going to flower with CFL soft whites, but I saw the 100 HPS light bulbs, they look like a regular light bulb, screws on any regular fixture and they don't need a ballast. I want to find out if anyone has tryed because I don't want to buy all that shit if its not going to work.
This a cool light w/built in ballast. May be too pricey for some, but would be great for 2 or 3 small plants. http://www.elights.com/100250hps.html To answer your question. It depends on the color temp. Is the 100w 2100k? If so, then it is fine for flower.
I actually saw them at a Do it center store here, I think they are pro-line from GE. I have to check if they are 2100k, if they are, I'll buy them and in a couple of weeks I'll post my results...