I assume by 150 watt CFL you mean 'equivalent to 150 watts of incandescent bulb lighting'. 150 (real) watt CFLs are huge, and expensive, like $80 per bulb or something. I have a couple of 150 watt (real) CFLs and they are like a foot long and each has its own reflector, and each puts out 12,000 lumens or around there. If you have real 150 watt and 100 watt CFLs, then it'd be kinda rough to just switch bulbs for flowering, simply because each set of bulbs would cost you several hundred dollars. If you have small 30-watt or 42-watt CFLs, which is what I suspect you have, then using warm bulbs for flowering makes total sense, since they're far cheaper.

As for preventing light leaks, Doran 8"x8" darkroom louvres are freaking wonderful. Yes, you can build your own baffled louvre, but odds are if you do, it will be bigger and less efficient at moving air than those made by Doran. On the other hand, it's hard to argue with free. But I have a couple of Doran louvres, and have zero regrets on buying them.

There is also such a thing as too much light, in terms of diminishing returns. If you pack 5 1000-watt lights into a 3'x3' area, you won't get 5 times the bud you would have gotten from one such light, whether you can handle the heat or not. You might not get any more bud at all, but your electric bill would definitely be much higher. Aim for 5,000 lumens per square foot. More than that won't do you much, if any, good. (Although keep in mind that the amount of light that reaches a particular point will be inversely proportional to the square of the distance from the light.)
jamstigator Reviewed by jamstigator on . Garden Knowm Hey dude...its me again...just a few questions again... 1- is there such a thing as 2 much light? i now have 2 150watt CFLs..2 100 watt CFLs and 2 75 watt CFLs...in my new grow box..*patented by me...made by my barehands*...they are over my plants by about 1-2 inches...with 2 4" fans constantly blowing on them...with on nice fan blowing outward for my ventalation..which brings me to my next question... 2-what do i use to cover the hole in my box for the ventalation fan?...i figure that your Rating: 5