Sand Sifting star diet?

[sfsuphysics]

I've had this sand sifting star in my tank easily over a year, it goes about above the sand, below the sand, even going so far as climbing the glass, now before you say "they can't do that" I'm fairly sure it's just clinging to particulate matter (algae strands) on the glass as it always falls off occasionally.

Now my question is what exactly does this eat? Sand critters? Detrius ? what? I'm moving my tank, and thinking about going with a little less sand (SSB instead of DSB) and I'm wondering if I should find a new home for him.

 

[bboy aqua]

I think they eat uneaten foods on/in the sand and you can occasionaly target feed them some frozen foods

if your going ssb,i would reccomend you remove it
although Im not an expert on stars