Played Coral MD During My Lunch Break

[GoodVybes]

Got a torch and hammer frag, both which came with something on their base. Any ideas what I'm looking at? Both frags were doing poorly, so during lunch today I decided to perform surgery and remove the critters. Not sure if the coral will make it, but figured they for sure wouldn't if I didn't get these things off:

Torch Hitchhiker

This thing has a hinged base and would open slightly when left undisturbed, but close quickly when motion or light was detected. It popped off the coral fairly painlessly, and on the underside I could see a fleshy worm-like thing. Left a nasty little hole in the coral that I sealed with super glue.

Hammer Hitchhiker

My hammer had two of these structures on the base. At night, I could see little hairs/tentacles coming out of the end of the tube (circled). This one I had to chisel away at, and the shell was definitely a spiral-shaped structure, where a found what appeared to be a small black worm at the end (no pictures, it was pretty destroyed). It too left some nasty marks in the coral skeleton.

Thanks in advance for any feedback. These were in the tank for a couple of months because I wasn't sure what I was looking at. Now I know better.

 

[Saltyreef]

Looks like a scallop

 

[GoodVybes]

The scallop-looking thing only had one fully formed hard shell which faced out. The third picture shows what the side facing the coral looked like. It was only half formed with the bottom half anchored to the coral base, providing the hinge (picture is actually upside down, sorry!). The critter was tucked in behind the half shell and would extend out when it opened up away from the coral base. The grey mass in the middle of the third picture is actually the critter in question. Almost looks like a snail body. Terrible photo, but it's the best I could do while trying to get the coral back in the tank.

 

[Maritimer]

Might be a vermetid snail.

Those guys seem to throw a few overlapping coils like the ones in your photo before growing their shells straight up into the water column by about half an inch or so. They secrete a "web" of mucus, which they use to trap small organic particles. Not dangerous-dangerous, but can often annoy corals - and reefers.

~B.

 

[Tired]

That first thing is some kind of bivalve, maybe an oyster. Some species have a very thin bottom shell, since the rock they're on protects them well enough. It shouldn't have been doing the coral any harm. I can't imagine it's parasitic- a parasitic oyster that eventually kills the host would then die, unable to move to new food.

The second thing... vermatid snail could be right. They annoy corals pretty badly when in close proximity, so that might actually have been harming the coral.