Hey,

Its been said, but yeah, 15 watt is no where near enough, nor will 30W of light.
Of course Wattage isn't anything to go on, nor is lumen, but as a rough guide I think you're looking for minimum 2000lumen per sq foot, or if you're not stuck in the 1960s thats roughly 20K lumen per 1 meter squared.
Again very rough math, an HPS or MH light puts out around 100 lumen per watt, CFLs slightly less. Its my understating that they're both more efficient (lumen per watt) than a standard fluorescent bulb. So if you have a 1m square area, you're looking at a 250W set up minimum. 400W would be better though.

Feel free to correct me if i'm wrong, no expert here :P

Goodluck,
phant0m
Phant0m Reviewed by Phant0m on . Closet grow question My brother is starting 3 clones in his closet lined with mylar, under a 15watt warm fluorescent, with 50/50 perlite/potting soil, as well as MG bloom fertilizer. No humidity dome, fan, etc. We would like to know if this will be an adequate set up for a first time grower? Rating: 5