Everything is picking on my corals...

[drm]

I have added some corals to my tank over the past few weeks...
green star polyp coral
yellow leather fiji coral
chili coral
blue mushrooms

Overall, they are looking "OK", although the green star polyp and the yellow coral have definite areas that look "injured".
I assume the green star polyp will be OK because it seems to be growing despite the abuse it has received.
But the yellow coral has what looks to be "bite marks" in it... little holes with a little bit of "fluff" like the inside of a pillow. And it is primarily remaining closed.
I have seen on all of my corals (except the mushrooms):
both peppermint shrimp(despite being well fed), dwarf red hermits, dwarf blue hermits, electric blue hermit, large turbo snail (on the GSP)... I also have a couple of "bad crabs" in my live rock that I have not been able to get rid of (the really hairy ones)... although I have not directly seen those crabs on my corals. (They rarely come that far out of the rock).
Perhaps some of these inverts are picking debris off of the corals, but something is clearly wounding it.
So will all of this work itself out? Do I need to do something to help the yellow fiji coral?
Tank info: 30gal, ph 8.1-8.2, SG 1.025, T 79, Amm 0, N.ite 0, N.ate 0, Ca 400, Iodine sufficient... clown, dottyback...
Thanks for your help!

 

[TCTFish]

Peppermint shrimp are more interested in the microorganisms that are on the coral that can harm the coral. It's the same for the most part with the reef hermits unless they can sense it is dying. That's their natural job...to clean up the sick, dying, and the dead.

You mentioned holes. Perhaps there's a type of worm burrowing in the coral??? Fireworms will do that...not to be confused with bristle worms. Bristle worms look like fireworms but really dull in their peachy pink color. Fireworms are thicker and more colorful...and much more of a threat to coral than bristle worms.

 

[drm]

I attached a picture to my initial post. I'm not sure how well you can see the bite marks. They really look like chunks were yanked off of the surface. I don't know really what fireworm holes would look like... I have not seen fireworms, but I know that would not be unusual. Also these don't to me seem to be all the way through, just superficial.
I'm assuming that with water changes and a good environment, it will heal... but I wanted to make sure that there was nothing else to do about it to help it heal. Also, of course, I would prefer that it not continue to happen.

 

[TCTFish]

That doesn't look like holes burrowed. A few things you can do. Watch the tank at night. You can use a red light to observe without disturbing the nocturnal creatures that are in there. Things come crawling out that you'd never thought you had. It is possible that there are microorganisms on the leather attracting the usual scavengers and it being so bad they could be damaging the flesh. Hard to tell at this point. For the coral you can isolate it in a bucket or a separate tank and do a bit of 'surgery' on it. You can pick off the bad pieces or use a stainless steel knife or sccissors and cut the damaged areas off. I mention stainless steel because it is a non oxide and less likely to 'burn' the coral. I would then recommend using a coral disinfectant dip as directed and place back in the tank. Make sure the dip specifies disinfectant. All this dip does is provide the coral a layer of slime to keep infection causing organisms out from damaged areas so it can heal.

Good luck and happy hunting.

BTW...you can cut coral and it'd be just fine. Leathers especially can heal up nicely. You can even cut them into a few pieces and have a few more...LOL. Soft coral like that are easy to propagate.