Browned out acro help

[caseyjones]

I have a few acros' that have browned out over the last few months. Is it possible that they weren't acclimated properly from a 20k to a 10k bulb? Would that mean that they turned brown as more xooanthelle was produced to act as a natural sun block? I thought I acclimated properly and attributed the brown to some high temps this summer but I haven't seen any change back to their colorful selfs. My parameters are right where they should be and i still get EXCELLENT growth, almost too fast. Any suggestions? I will post pics later.

 

[slojmn]

Lighting definately plays a big role in coloration and growth. Traditionally 20k gives some great colors but very slow growth and 10k gives better growth but you may lose some color, especially in corals that are use to the 20k spectrum. Nutrients in the system also contribute to brown outs in corals. The higher the nutrient load the browner the corals...Many corals coming from online vendors are under 20k 1000w MH, color shifts are expected when you can't match that lighting intensity and every tank is different as far as nutrient load and params. Have you considered going to a 14k bulb?? Some color may return and growth wont slow as much as with the 20k bulbs. You may also want to check you PO4's.

 

[GMAX]

My opinion would be its more likely a nutrient issue. What are your reading on NO3 and PO4?

 

[caseyjones]

Thanks for everyone's help...I'm inclined to believe its a nutrient issue too although I would think if anything my nutrient levels were too low. Both my phosphate and nitrates are at 0...i run a phosban reactor and in my refuge is a DSB. I have sand in my main tank although it is purely for looks, only an inch or two deep. I'm using an Iwaki 30 as a return pump and a MJ1200(not modded yet) for current, its only a 50 breeder. How high would you put a 400 over the tank? Also, how high would you try the acros?

 

[kybreos]

400 watt!! maybe 4 to 5 ft, youre better off with a 250 watt 14k or 20k about 6-10 inches over imo.