cmh and hps bulbs
I recently purchased a Ceramic Metal Halide bulb and compared it with the HPS bulb I have, in the course of two weeks, one week with each i'm amazed at how well the CMH bulb did.
I bought one of the Philips MasterColor 400W bulb, under a 5x5 grow area with cucumbers, jalapenos, bell peppers, habaneros, 5 tomato plants i now have all of them fruiting and in one week i've seen 2 inch's of growth on my bell pepper plant!
This bulb is truly one of the best things i've ever found for growing, the HPS bulb actually caused my habaneros to begin to wilt and leaves fall off, the next week when I put on the CMH bulb the whole thing not only grew about a half an inch it put off new bottom leaves!
I truly believe this is probably the best grow light period.