coral looks like its blistering - is it even possible

[becketd]

the other day i noticed one of my sps corals was looking like it was swelling....at the time i thought it was going to start froming a new branch...but lastnight i looked at it and noticed that the whole side of that particular coral was starting to swell...so i took my tongs to touch it and see if it was hard...i was very suprise when i found out it was soft....almost like how skin gets a blister.....very weird...i have made a couple of changes to the tank recently..one of them being new MH bulbs...i do it at the start of every year...so i was thinking it was from to much to soon...i cut my photoperiod back to only 4 to 5 hrs a day....i pointed a power head in that direction and thought maybe it was blowing to much water on it or something...i really dont know whats going on thou...anyone with any ideas....i really dont want to loose this coral...thanks david

[landlord]

If you haven't already posted this in the SPS forum (with a picture, if possible) that might get you a quicker response.

[becketd]

prob right..no camera...

[seapug]

I've seen many of my acros do this during the day. As long as the tissue isn't peeling off I think it's just a sign they are healthy, growing and expanding their polyps. I certainly would poke or pick at them when they do it.