14000k 250W MH...Supplement with Actinic?


New member
I am going to be retrofitting a dual 250w M58 MH 14000k or 20000k setup. I was wondering a couple of things.

I am curious if first I should purchase the 14000k or 20000k bulbs? I realize that the 20000k has some more blue in it, but I was wondering does that extra blue spectrum mean that I don't have to supplement with actinic? If I go with the 14000K should I supplement with actinics because the color temperature is different?

My long term plan is to keep sps, lps, & some softies. They are absolutely beautiful. So I want to go with the right bulbs to get the job done. So which color temperature would you guys choose if it was up to you? If you have any comparison pics, that would help out a lot.

Thanks in advance!


In Memoriam
It depends on the look that you want. 14k hamiltons and phoenix bulbs look fine (too me) without actinic supplementation, but 20K xms look too blue and actually need 10K supplementation (to me), so it is all relative. Look at Sanjays spectral charts, they show how much blue each lamp puts out. Check out the top of this forums "frequently asked lighting" thread.

old salty

Premium Member
I'm using Giessemann 14K bulbs with no supplementation and have no issue with the colors. I guess it's all about how you want things to look. In my eyes, 20K bulbs don't look good at all; to others, they wouldn't have it any other way.


New member
IMO 14K bulbs like Phoenix, which are pretty blue, look great with actinic supplementation, and by that, I mean real actinic, 420 nm bulbs like UVL Super Actinics. The 14K spectral plots show very little output at 420, which seems to be an ideal wavelength for flourescence in many corals.