First off, I apologize for making yet another topic on this. I did a search and found some usefull information, but not enough to make me feel confident on my own.
I have a 29 gallon tank that I'm starting to plant. It's got a lot of Anacharis and I'm going to be adding other low/mid-light plants to that in the future. My current ballast/light is a simple 20W fluorescent. I'm not sure what the rating on the bulb is, aside from being 20 watts. It may be an awesome bulb, but since it came with the hood, I doubt it (plus, my plants aren't as "full" as they could be).
Anyway, what is the best spectrum to look for? In the store I went last night, there was an 18000K, a 1000K, a 6800K, and a 4200K. I will be getting two bulbs and I'll be using a twin tube strip light fixture. I'll have roughly 1.4 WPG