Unhappy Hammer. Thoughts?

[Jamie9]

One of my hammers has been quite unhappy the last 4 days. It's been a little more closed up each day until today, where it looks as shown in the photo below. No recent changes to the tank. Parameters have been pretty steady lately at about 35 ppm (nitrate), 0.35 ppm (phosphate), 8.4 dkH (Alk), 1300 ppm (Mag), 470 ppm (Ca). The hammer next to it is just as fluffy as ever. No recent additions to the tank or changes to lighting. Any thoughts on what I should do other than keep an eye on it? The hammer has been happy in that location since I put it there in February of this year. I have not noticed any obvious pests...but if somebody else sees one on this photo, let me know! Thanks!

 

[Teddy99]

did the clownfish bother it the last days ? Like cuddling a lot or biting the polyps?
Just a first idea as it is close to the coral.

 

[Jamie9]

Not that I'm aware of. Those jokers just like to put on a show whenever I walk up and point the camera at something!

One thing I noticed today though. There's been a tuft of green hair algae growing off that hammer for months. I've just left it because I didn't want to irritate the thing. It was still there yesterday after 3 days of it getting more and more closed up. Today it seems to be gone, so it's likely that earlier this morning either a snail or hermit crab were up on there.

 

[Teddy99]

I had my Mithrax eating algae growing on an euphyllia Skeleton and irritating it. It might be something like that, but can be something different, too. I would watch and observe this coral and the others the next days.

 

[Jamie9]

I had my Mithrax eating algae growing on an euphyllia Skeleton and irritating it. It might be something like that, but can be something different, too. I would watch and observe this coral and the others the next days.

Thanks, good thought. Maybe I'll take out the red flashlight and have a look at night and see if anything is poking around. I don't think I have any crabs...but I've thought that several times in the past and then wound up having to trap gorilla crabs and yank them out! I have recently gotten rid of most of my green hair algae...so it is possible that has made this coral a bit of a target since it had a nice strand on it.