I have noticed holes developing in this Acan coral over the past 48 hours. The coral survived a red slime bacterial infection treated successfully two months ago. Was actually showing signs of growth since then until I noticed these holes developing. I was instructed by the shop that services my tank to dip it in a solution consisting of a mixture of Reef dip, coral Rx and flatworm exit. During this process I noticed that the defects go all the way through the skeleton of the creature to the other side? I did not notice any parasites escape. I am wondering if anyone has seen this and what the cause might be. I tried to attach some pictures. The tank is 220 gal, most coral doing very well as are 5 tangs, 2 clowns, 10 chromis, single banded shrimp. Last check 2 days ago paramaters showed high Magnesium 1600, Ca 460, Alk 10.4. Thanks in advance.