How close to the plants?

[Reverend Willis]

Hi guys. I want to add another light to my 250w cfls. Since I'm limited to headroom in my growbox, I'm wondering how far away from the top of the plants I would need to keep an HPS? How about an MH?

Is there a general rule of thumb for distance of different type lights?

I found Mutt's FAQ on lights but the chart was fuzzy (OK, maybe my brain was fuzzy too). It looked like an 250w HPS could be about 6 inches above the plants. It sounds like an HPS would compliment the CFLs I have already. I could veg under the CFLs and then throw them under the HPS to flower -- and use the CFLs for supplemental lighting on the sides. Does that sound like a sensible, workable plan to maximize whatever I'm growin' in my doobage patch?

What say ye, oh gurus of dope? ... not to imply that you are dopey gurus.
Thanks
Rev

 

[Reverend Willis]

Another read through the FAQ helped immensely. Perhaps I was less stoned this time around. After digesting lots of info, I have decided to add a 400w HPS to my growroom. I shopped around and the 400w is $10 less than the 250w. I think the $140 investment will be well worth the outlay.
Okay, I'm kinda thinking out loud to myself and talking the the little people in my head. It's cool. We're all in agreement on this decision.

Any words of wisdom on specific types of 400w bulbs? Or will the standard bulb work fine?

How many plants (in 5-gal pots) will fit under a 400w?

 

[Hick]

mornin' reverand..."IMHO", benefits that "I" have observed from conversion bulbs/enhanced spectrum bulbs, do not justify the added cost. I recently purchased a 1k HPS for under $60, while the last "Hortilux" enhanced spectrum 1k bulb cost me nearlly $200. I was sadly disapointed with the results.

 

[Weeddog]

I keep my 400w hps in the neighborhood of 12 to 16 inches above the tops of the plants. Hold your hand under the lights at the top of the plants and if its too warm, you are too close.

 

[Reverend Willis]

Hick... Thanks for that money-saving advice. Many of those "upgraded - specialty" lamps are through the roof price-wise. You can buy 2 total systems for the price of one bulb.

Weeddog... Thanks for that info. That's a common-sense approach to proper distance that I can relate to.

The deal is done. I've ordered my 400w HPS and it should be here in 2-3 days. I'm more excited than a horsefly in a cow barn. Now it's time to do some serious rearranging in my grow room/closet. My (1) WW and (1) WWxBB ladies are 4 weeks into flowering so they'll have 4-5 weeks under the new HPS.
Thanks guys