Why is my Star's legs getting stumpier and stumpier?

[riemannp]

I have a sand sifting star who appears to be ok in general except each of his legs has gradualy become more and more stubby (or stumpy). What is causing this? Photo is a healthy sand sifting star; I'll try to get a photo of my star. Thanks in advance!

 

[Jozee]

Does it have enough to eat? Once they have depleted their food supply in the sand bed, they can start to melt away.

 

[Derbird]

Do you have something in your tank that might pick on the star? First guess with out a picture would be some one nipping the tips.

 

[riemannp]

Thanks for the feedback. I did some research and find the deterioration can be a sign of starvation, which means the star has munched away my DSB infauna to such a point that the infauna population can't sustain his appetite (at least this is my belief). I realize now it is a mistake to have him in there.