Lighting, Opinions, and Coral Growth?

[gooyferret]

So.. one of my MH bulbs burned out on me right now!
Im running 3 - 250watt Electronic Coralvue Ballasts, 3 - 14k MH bulbs Coralvue. This is on a 125gal 6 feet long.

Some people say to run 10k bulbs and attinic supplement and you get better growth out of your corals. What do you guys think? Should i replace the 1 burned out bulb for a 10k, and then when i switch the other 2 in 6 months make them 10k and add attinic or just stay with the 14k?

Does 10k really offer a "better" par for coral growth?

Switching 1 bulb in the middle to a 10k and having 2 14k on the on the sides would it look weird in the tank?

What bulbs do you guys use and recommend?

TIA and lets get some opionions and ideas!

[melosu58]

Moved to General hardware and equipment discussion.

[Ziggy953]

Apparently there is a debate raging on the net right now about what color temp provides the best growth. I've been running MHs for almost 3 years now and I've used every color temp out there and seen good growth in all of them. I've bounced from brand to brand and never been disappointed. Some say you have to spend tons on each bulb and get the brand name others say it doesn't matter. I tend to agree with the latter as I've tried expensive bulbs and I've tried cheap eBay bulbs. Your lighting is only one piece to the growth puzzle. You need excellent water conditions, flow and light for that awesome growth (there are other variables in there as well but those are the basics). I have a 120g tank with dual 250W 14,000K XM bulbs with 2x54w T5 Actinics and 2x110 VHO actinics. The result is a nice crisp white look with excellent color in my corals. Now I've only been running the 14,000K XMs for a few weeks and can't really speak to the speed of the growth but I can say that I'm seeing good growth in most all my SPS corals. On the flip side I have a 55g frag tank plumbed into my system and it has cheap ebay bulbs over it right now that are 20,000K and the growth of my SPS is insane. I've run 10,000K on the frag tank with the same results. These are 175W bulbs btw.

Bottom line to this little story is this. Read the tests and all the information you can on bulbs, reflectors and par, but in the end make your decision based on what you want your tank to look like. You will see growth regardless of the bulb choice as has been my experience.

Hope that helps.

[ccCapt]

Ahhhh...lighting, one of my favorite subjects.

Does 10k really offer a "better" par for coral growth?

It depends on the brand of bulb as far as PAR. Many thing influence coral growth besides lighting, but if the conditions in 2 tanks were exactly the same except for lighting, the tank with more PAR "should" have better coral growth....depending on the type of coral. Some don't like lots of light.

When I am looking at bulbs, I use Sanjay Joshi's Lighting site. Sanjay tested hundred of different MH bulbs and the results are posted there. Keep in mind, he tested all the bulbs out of water with no reflector, but if with your particular tank setup and reflectors, you lose for example 20% of the output, you will lose 20% on every bulb.
Here are the Performace Results for all 250w MH bulbs tested. When you look at the chart, look at PPFD (Photosynthetic Photon Flux Density) which is the basically amount of usable light for coral the bulb puts out and CCT (Correlated Color Temperature) which is the actual K temp of the bulb as tested.
You use Coralvue ballasts, which are similar to IceCap ballasts, so as an example, here the difference is a few SE bulbs all run with an IceCap ballast.
Your current bulb - Coralvue 15K: 47 PPFD
Coralvue 10K: 86 PPFD
XM 15K: 47 PPFD
XM 10K: 115 PPFD
SPS 10K: 90 PPFD
Aquaconnect 14K: 83 PPFD

I use 3 175w Iwasaki 15K over my 6' 125. They are 86 PPFD, so basically I am using less electricity and getting more PPFD than many 250's.

[gooyferret]

Thanks for the info guys! Keep it coming just trying to get others input as to par and kelvin of bulbs and brands prefered.