View Full Version : Growing Frags, optimal PAR and color temp

08/02/2010, 01:17 PM
I understand that coral use the zoanthellea (sp) to get nutrients from and that those bacteria use the PUR (photosynthetic usable radiation), of around 420-500nm. I am looking at beefing up my tank 420 range simply for a bluer look. Its in my living room lol!

I need to replace two 175W MHs and am considering taking both to 20k and using 2 True Actinics in the hood as well. Does anyone know if 14K-15K may provide a better growth rate for the bacteria on hard corals?

As far as I know the PAR (Parenthetically active radiation) is better with lower K value, but the PUR is almost unchanged, loss of 1% or so. And if they can't use any of the additional light spectrum I may as well make it look cool haha.

Thanks in advance

08/02/2010, 01:18 PM
10k will provide much better growth than 20k, while 20k is much bluer.

Phoenix 14k's are a pretty good balance, IMO.

08/02/2010, 01:32 PM
What about Reeflux 12Ks? I'm running those and they look veeerrry similar to the color I was getting out of the 20Ks. I dont know about the growth though. I'm using crappy parabolic reflectors, but will be upgrading to Lumenmax Elites soon enough.

08/02/2010, 04:09 PM
I got the best growth and brightest true color with 10k. I use 14K now, but that is for the better asthetic appeal of the entire tank itself. My frag tank still has 10k for color and growth.

08/02/2010, 05:07 PM
I used 250w 10K reeflux on icecaps for 4 or 5 years and while I always have had good growth,
2 months ago I changed to 250w radiums on a hamilton m80 ballasts.
and I have seen a spurt of growth on all of my sps.
Especially on some stuff like my carolinianas and a poker star monti which were kinda just sitting there...
The lps not so much but still growing.
No proof of anything here, just an observation.

Oh yea, the reefluxes were about 5 months old and I ususally changed at about 9 months.