Odd acan behavior

[Llg]

I have about 5 acans in the tank. I have had an acan for about 3 months. It has been receeding on one side, but it is also growing new heads. In fact, one head is right next to where the tissue was receeding. Parameters have been fairly stable since it was added. I have been dealing with dinos off and on the last 6 weeks and found that my salifert test was telling me there was PO, but when Ibordered the Hannah tester it showed 0, so I have been dosing to keep PO up. I noticed the receeding tissue around the time the dinos showed up and I had finished a 3 day blackout. That was also when the new heads showed up. I had noticed a vermetid snail on that spot when the recession started and I clipped it off. It has been slowly receeding more since then. The acan itself is puffy and eats well and extends at night. I feed AB+ every other day and spot feed LFS to it.

Is it normal for it to do this? The skeleton is very visible on the side as bright white.

No 2-5 ppm
PO .003 to .08
PH 8.2
Sal 10.26
CA 480
Alk 8.1 to 8.4
Temp 77.8 to 78.5
Mg 1480

 

[mdrieder]

There's a lot going on here that may be an issue. Phosphate swings will certainly tick things off but Id probably blame the vermetid snail. Their mucus nets, IME will melt LPS heads if they get stuck on there. Once that happens it may recover and it may not. With Acans once I see bone I consider that polyp lost.