lighting spectrums

[crystalreef]

I am going to be keeping sps corals very soon.
what I need to know is can I keep any sps coral under 20k 400w (eg. pink,blue,purple acro.) or will 10k be better? /ubbthreads/images/graemlins/confused.gif

[tendar]

There are a number of people running the 20k radiums for sps. You will get more light and par from a 10k but 20K seem to work well.