10,000 or 12,000 K ?

[klg1824]

when i first started my 150 reef, i had 300 watts of white VHO, and about 150 actinic. because of a small fire in the hood, i upgraded to Metal Halides. In my 5 ft. long tank, I have 3 -250 watt 10,000K with 300 watts actinic. the light now seems much brighter and whiter than the old setup which gave a nice blue sheen. I want that sheen back so I think changing hte bulbs to 12,000K (250watt) will do the trick. Is my information correct and are 12,000K bulbs as good as 10,000K concerning hte health of the corals?? Please advise before I do something rash....
Thanks

[loganj]

12k bulbs will have slightly less intensity than 10k. I think the UV output will be slightly higher also. They should have a bit more blue though. What brand bulbs are you using now? Different brand bulbs will give you different results. You can also get a 15k bulb. Hara is using 20k HQI's and reports good coral growth with them although some of the blue tinge wore off as the bulbs burned in.

[captivereefs]

Plus I have heard alot of negatives about the sunburst 12k's. They tend to burn out prematurely. I would go with a good quality 10k bulb.

[SquishyFish]

With m/h bulbs there is a trade off on color and par. 10k bulbs have a higher par than say 60k bulb....the trade off is that a 10k usually has less blue in it and can even have a yellow tint. What happens when you mix yellow (10k) and blue (actinic)? You get green. So it can be a balancing act. 10k are definately the way to go if your wanting alot of coral growth. 20k are the way to go if your wanting a blue sheen on the tank. The 20k's are not bad..just 2nd best.

HTH,

Squishy

[Biggen]

I run a 20K Hamilton bulb over my tank. I just finished building my canopy which includes 2X55w PC 03 plus my 20K MH bulb. I have been doing so much reading that leads me to believe that lighting that favors in the blue color of the spectrum really improves coral growth and coloration.

However, in the end, I think it is simply personal preference that dictates what bulbs to use over the tank. If you are looking to get that "blue sheen" back, I would go with a Hamilton 14K bulb. Not too blue and not too white. If you wanna get a little more blue, go with a 20K bulb.

[loganj]

I've heard the same things about the Sunburst. I was actually referring to a Coral Vue bulb in either the 12k or 15k.

[Hara]

Originally Posted by SquishyFish

10k are definately the way to go if your wanting alot of coral growth. 20k are the way to go if your wanting a blue sheen on the tank. The 20k's are not bad..just 2nd best.

HTH,

Squishy

I disagree with your assessment. I had the 10k bulbs for a year, I switched to the 20k and it is a definite improvement in coral health, growth and appearance. This is MY experience, maybe different than yours, but I would not call them second best by any means.