What MH colour temp for Veg? 6500K 10000K?

I was just about to buy 5 42W daylight CFLs for my little veg cab, but then decided I should check that old security light in my back yard that was there when I moved in, that I don't use. It works great, and after trekking up through the bush I was pleased to find it was 250W! Perfect for my space and better than the CFLs I'm sure.

Now, I figure the bulb, though it works, is probably pretty old. What's my best bet for a replacement? I know that the plants use blue for veg, and I've seen those really blue 10000K+ aquarium bulbs. Are they better than a 5000K or 6000K because of the more blue? I'd think so, but I don't see anyone using them.

Just curious what I should go with.

no one responded because no one knows shit about aquarium lights in here. yeah, they will work but you might want to supplement some red lights in there.

10k is UV light, id only run it the last few weeks of flower. otherwise 6.4-6.5k for most of veg.

6500k will do ya fine for vegging

5000k is the best or any where near that can be used all the way throughout the grow, 10000k does not put off UV unless, well, there are varoius situations where it would but let not get into that.. beside the glass around a single ended bulb filter uv and if you have it in a reflector with glass this further dampens the uv.

but anyways back to 10000k it would be useless in veg and difficult to grow with it has no red spectrum so you would have unbalanced and slow growth.


6500k, 6700 k are really the best for veg growth, 5500k-4000k for flower (as far as halide goes)

i think i responded to this exact thread 3 days ago.