Strange pattern of Acro death

[JohDwyer]

The short version for those who like cutting to the chase: My Acros display a very consistent pattern of death. They do well for a few weeks, then polyp extension reduces sharply. After that, they lighten in color starting from the base. Then they very slowly, over weeks, recede from base to tip. This has happened with 2 different garf bonsai frags and a Bali green Slimer stag which I was told were hardy for Acropora.

I have a 40 gallon Nuvo fusion lit by a reef breeders photon V2 mounted 15 inches above the water running 70% blues, 20% whites, and 5% red and green. Parameters are VERY STABLE. Alk: 8.7-9.1 / Cal 500/ Mg 1450 Nitrate 3.0 Phosphate 0.00 - I have a refugium (producing a lot of cheato and green hair algae) and am currently dealing with a small bubble algae problem so I assume there is phosphate. I am running a skimmer and Chemi pure blue for 35 gal. My livestock is one serpent star, a juvenile melanarus, a yellow clown gobi, a yellow watchman gobi, a small clown, and a bangai cardinal. The tank is 10 months old and I dose ALL FOR REEF. I have been successful with all LPS I've tried and all SPS from montis to birdsnest. But all my acros die slowly.

Any advice is welcome.

 

[((FORDTECH))]

The short version for those who like cutting to the chase: My Acros display a very consistent pattern of death. They do well for a few weeks, then polyp extension reduces sharply. After that, they lighten in color starting from the base. Then they very slowly, over weeks, recede from base to tip. This has happened with 2 different garf bonsai frags and a Bali green Slimer stag which I was told were hardy for Acropora.

I have a 40 gallon Nuvo fusion lit by a reef breeders photon V2 mounted 15 inches above the water running 70% blues, 20% whites, and 5% red and green. Parameters are VERY STABLE. Alk: 8.7-9.1 / Cal 500/ Mg 1450 Nitrate 3.0 Phosphate 0.00 - I have a refugium (producing a lot of cheato and green hair algae) and am currently dealing with a small bubble algae problem so I assume there is phosphate. I am running a skimmer and Chemi pure blue for 35 gal. My livestock is one serpent star, a juvenile melanarus, a yellow clown gobi, a yellow watchman gobi, a small clown, and a bangai cardinal. The tank is 10 months old and I dose ALL FOR REEF. I have been successful with all LPS I've tried and all SPS from montis to birdsnest. But all my acros die slowly.

Any advice is welcome.

Well the obvious 0 phosphate sticks out to me. I’m sure many will agree.

 

[((FORDTECH))]

I run my phosphates at .25 and nitrates at 20 and all my acros love it

 

[mikereefing]

I'm no expert but I can definitely say that I've had the exact issues you've had. I also have bubble algae as well even at lower phos levels. However, I can say with certainty about MY tank, is that whenever I let my refugium run wild too much and have <0.03 phosphate measured on my Hanna checker, my corals look terrible. I know there's some traces of phosphate since there's algae growing, but my LPS and SPS tell the same story each time. At this point, I've gone through this cycle so many times that I know exactly what's annoying my SPS. I have a PC rainbow colony that lost 99% of the tissue...with literally 2 polyps left. A week later (today), there are 4 polyps left and it's growing back. All I did was dose a little NeoPhos to keep my levels steady at 0.03-0.05 and add some red sea trace elements.