Ok, I switched out 2 bulbs and changed them to the 14k Hamilton's will see how the corals do. I do like the look of the Hamilton's though.

http://i125.photobucket.com/albums/p...res2007018.jpg

Give you a heads up on coral color with higher K values.

If you have 10K lights, the corals will naturally color up. They will sustain that colour as long as you keep the 10K lights on. As soon as you move away from 10 to 20K, the corals will regain their brown zoanthallae.. but because of the blue hues, the corals may seem colourful. I call it the fake colour..

I recently did a test in my tank regarding this.. and proved that corals brown out with 20K lighting. They look colourful, but they really aren't.

What I have done to my tank is run 2 10K MHs during the day (while I am out, at work, etc), and then at night 1 14K MH. This way my corals retain their colour and growth, and at night the tank looks nice and blue.

I've used almost every kelvin of bulb and whatage/type now. I honestly think for the most part, what chemistry and light intensity is going to be the biggest influence as far as pigment colouration. I would just find a reputable bulb that you like the colour of.

This sounds like getting the best of both worlds. Great tip!

I've tried almost every type of 14k SE bulb there is and I always go back to EVC's. They are awesome in color and put out a fair amount of light. (a hair better than 14k hammy's, with quite a bit more blue)

Not to familar with EVC's are they 14k as well?? Another quick question in regards to Sanjay's site on RC what is CCT as opposed to par. The reason I ask is that the Giesmann 13k bulbs have very high cct numbers as opposed to other bulbs.

You can get EVC's in 10k, 14k, & 20k. I run the 14's. (available through Ocean Encounter)

Ribber, CCT is the correlated color temperature of the bulb.If you have a bulb that is rated say 10K, that rating isn't always (seldom maybe) what the manufacturers state,plus over time the color of a bulb will shift.Sanjays CCT is the color temp of the bulb at the time of the test.