starfish looks like crap

[susie&jeran]

I have an Orange Lankia Starfish that I've had for about a month and now he's not doing so well. One of his legs had a little chunk missing and now it's spread really bad. I thought maybe our Coral Banded Shrimp did it, but the star fish always stays at the top of the tank and I don't see our Shrimp getting up there just to nip at him.
I've heard that liverock could have something to do with it, but we have live rock & lots of live sand. Our Sandsifting starfish is doing amazing - he's getting so huge. Our water levels are PERFECT & our salinity is where it should be (we brought it up after 1 of our urchins died). Is there anything we should do? Any tips/ideas?
I also heard that you can cut the rotting part of the leg off and a new healthy one will grow back? And oils on your fingers can kill them if you touch them?

 

[nick76]

How big is the tank?
How long has it been running?
What is the exact salinity?
How much LR and LS do u have?

 

[garnet13aj]

Also, how long did you acclimate the star for, using what method?

 

[ophiura]

Please post your SPECIFIC tank parameters.
What is "perfect" for fish is often fatal for such stars.
Based on the time frame this is without a doubt acclimation shock, IMO.