DIY LED Hood: Prebuild Thoughts...

[Lampshade]

on this topic, have you seen any dimming programs for Arduino using a varable voltage output instead of PWMs?

Arduino's can't output a variable voltage, but you can buy filters that will change PWM outputs to a 0-5v or 0-10V. check out:http://www.nano-reef.com/forums/inde...owtopic=230743 - different values work for different pulse widths, there's online calculators to see what you need.

As for heatsinks you are right, overbuilt is no problem at all with me either. I'm not going to go buy 60" of 10" pure aluminum heat sink with 1.5": fins now though, after calculating it a bare piece of aluminum with a fan on it would work "in theory". I'm going to probably run aluminum channel, and also I'm going to have an arduino running my LED's, so for $2.50 i can get a thermometer on the heatsink to shutoff for overheating, i'll proably put 4-5 of them on just to be sure.