How many Kelvin?>>>>>>>>>>>>

[follow3]

I am setting up a tank for all types of corals and also a clam.

What Kelvin do I need asuming I am going to use the MH and no flourescents for actinic?

Thanks,
Steve

 

[Mariner]

Anywhere from 6,500k to 20,000k will work. The lower the Kelvin, the more yellow the color -- higher Kelvin is bluer. All else being equal, things tend to grow quicker under lower Kelvin but have better color under higher Kelvin. I think the majority of reefers use lights in the 10k to 15k range. A lot of it just depends on your personal preference.
This thread has some nice pics of the effects of different Kelvin.
HTH,
Mariner