Lighting photoperiod

[redwingrob40]

I have a question about lighting photo-period for SPS. I am currently running a 4 bulb aquaticilife fixture with ATI bulbs that were replaced a little over a month ago. They are AB special, B+, Purple+, B +. I run them on a 12 hour cycle with the B+ coming on for two before and after the daylights, and all 4 bulbs running for 8 hours.

Does this sound like a reasonable photo period? Because I have recently noticed my corraline bleaching, and loss in color intensity in some of my SPS.

Params:
Are- Alk- 8.4 dkh, Ca- 480, Mg- 1430, temp 78-79

 

[milesofreefs]

what size tank?

i run the same lighting time on my forty breeder and haven't had any problems with bleaching.

what about nitrates and phos? where are those at?

 

[redwingrob40]

It's a 55 gal. The nitrates have read 0 on API for a while now, and phosphate, last time I had the LFS test and it came up undetectable on API, and Hagen test kits. Would GFO do this? I started running GFO too, about a month ago for algae issues in the tank. Followed the directions on the BRS GFO to start slowly and then slowly add more.

 

[milesofreefs]

im not to sure... ive never added gfo to my tank or looked anything up on it.

So this may be way off track...
If GFO acts anything like carbon... Meaning, makes water clearer blah blah blah...
Ive read that the change in water clarity can cause them to bleaching.....

water gets clear, lights get more intense on the corals, to fast. then they bleach.

 

[redwingrob40]

Yeah good points, I tired to follow the directions for both GFO and Carbon to ensure that I started slowly and even added a little bit less than the recommended starting doses.... Guess I could take the GFO and carbon offline and see what happens? I may be way wrong but I don't think that that is it??

From what I've read here on RC it seems like it may be an intensity issue?? So, would cutting the photoperiod help? Or maybe adjusting to run the blues longer and the daylights less? Or maybe cut down the 12 hours all together?