That may work (algae pellets). I guess you have baby clams. Clams sift through the water in the sand that is brought in by the waves. I think they use the "neck" like a straw. It may be tough to duplicate that. They most likely will die before you find out. Real stanky when they do.

I would guess you could liquify some frozen small food [plankton, brine shrimp, veggies] and use a turkey baster to squirt the food to them.

That's a great idea james ny,
Thanks!
I will also crushed fish food pellets.
Thanks,
Adrian