bleaching issues

[paxthemax89]

I have a birdsnest and a plum crazy acro that have started to bleach. I only have 2 tests I can run right now due to being cut off from the mainland due to Sandy. The calcium is at 480ppm, ph 8.1 and salinity is 1.026. My lights havent changed im running 3 blue actinic and 1 10k 54w t5ho bulbs with 8 months use. The photo period is from 1200-2000 everyday. All the other corals are still growing like crazy and my bta is bubbling up now. I have had the corals for 8-9 months and this just showed up about a week ago. What are some possible reasons they are bleaching.

Thank you for your help.

 

[Finland]

Main causes for bleaching would be low nutrient levels, poor light acclimation, water being stripped of nutrients quickly(gfo or cabon dosing), some outside contaminant, or lack of a trace element needed by that coral. I seriously bleached a few of my corals a few times, once by adding too much gfo to the reactor and another time by using too much biopellets. Also, if my alk gets out of whack, I will lose color. That's all I can think of right now.

 

[hypnoj]

Main causes for bleaching would be low nutrient levels, poor light acclimation, water being stripped of nutrients quickly(gfo or cabon dosing), some outside contaminant, or lack of a trace element needed by that coral. I seriously bleached a few of my corals a few times, once by adding too much gfo to the reactor and another time by using too much biopellets. Also, if my alk gets out of whack, I will lose color. That's all I can think of right now.

I agree with this as well. Bleaching for me always occurs when I strip my tank of nutrients. I run GFO and biopellets; too much of either of these will do it. My first foray into LED's did it too, but bulb changes for my T5's or MH's has not done it yet.