Such a thing as too much light?

[Enigma]

I considered one of the Steve's LED kits. He's got an actual NC12 retrofit kit, and the price is good. He's also got some great LED colours (particularly violet), that I would like to try.

As this is for my contest tank, I want to be sure I can do it myself (though your offer of assistance is greatly appreciated and I'm sure some day I will request it . . . For LEDs or fixing my skimmer plumbing. ).