Thanks Jim, I appreciate the encouragement. From the height I am putting my screen I have 16 inches till my lights are maxed out on adj. I think I will be getting my screen today and flipping in the next 2-3 days. What do you use for screen? I can get some metal screen with 2X3 inch openings. I also have thought about a pvc frame with screws in it and string ran between the screws. One other thing, I know you have said anything more than 300 watts you get diminishing returns. Do you mean in relation to heat, cost, or what? I have exactly enough room to put 3 bulbs on my mounting board. What do you think? 375 isn't that much over 300 and I have no problem with heat. LMK what you think.
Jack
For my screen, I use plastic mesh/fencing, bought at a garden center. Each opening is 2 x 2.5 inches. I cut out a section of mesh about 2 inches shorter than the length and width of my box, then put a ring screw in each of the four corners of my box at the height I wanted the screen (about 15 inches high). I then used zip ties to tie the corners of the screen to each ring screw, pulling the screen tight into each of the four corners so there's minimal vertical 'give' in the middle of the screen.
Here's a pic of one of the front right corner of my box:
As for adding more light, assuming you can manage the heat output, by all means go ahead and add as much as you can afford and/or have space for. The 'saturation point' I sometimes refer to simply means I believe you reach a stage where you're spending a similar amount of money on bulbs and cooling (and electricity) where CFLs stop being the best option. There is certainly nothing wrong with using 500W of CFLs, but I think that once you pay for cables, sockets, fans, reflectors, and the bulbs themselves (of each spectrum), you'd be just as well buying a single 400W MH/HPS setup. Plus, with CFLs, there's the added maintenance issue of constantly having to train your plant(s) to keep each top to within 2 inches of the closest light source. Plants under HPS can grow more 'freely' without having to be micromanaged on a daily basis. I feel that once you get past a certain total wattage of CFL (usually around 400), it isn't that much cheaper (all told) than an HPS of similar watts, and less grow management involved. Arguably, flowers are more dense with the increased lumen intensity from HPS as well.
All that said, the beauty with CFLs is that you can add supplemental bulbs as your budget allows, which means that your initial outlay can be significantly lower than with other types of lighting. Every time payday rolls around (or as the plant gets bigger), you can go out and buy more bulbs. With MH/HPS, you're heavily invested from the start, and cooling is more expensive as HPS throws out more heat. Most of all, though, you usually need more height to your grow space with HPS than with CFLs, so that bounces micro-growers and most cabinet growers from the HPS party.
Sorry for the long-winder answer. If you can afford them, have space and can cool them, certainly add more bulbs. Your plant will respond well.
Jim
Got to get busy building my screen. I'm going about 12 inches above the media and at this rate it will be there in a week.
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