Red Studded General Starfish limb starting to white out

[RealWorld]

Can anyone tell me what’s wrong with my starfish. It still moves around the tank but one of his limbs is showing sign of deterioration, and the knobs on its limb are whitening out and falling off. Any suggestions for what is causing this and what can be done (if any) would be appreciated. See attached picture.

 

[monkeyCmonkeyDo]

Water quality. They are very finicky to swings in ph. Salinity. Alk.
Youd say your tank is very stable?
D

 

[RealWorld]

Yes, all water parameters are normal. I was more concerned about whatever he’s got affecting the fish. Are those types of diseases transferable across species, i.e., inverts to fish and vice versa ?

 

[RealWorld]

 

[NeonRabbit221B]

Honestly sea stars are best left in the ocean. They are hard to keep due to their diet... My guess is that it is starving to death.

More info please. How big is the tank? How long has it been setup?