None of the worms in my tank have bothered my T. Crocea, and some of them are over 6" long, the biggest is over a foot! My yellow cuke is no problem, as are none of my snails although they do occasionally crawl on the shell to graze.
The biggest threat to clams are boring snails that arrive as hitchhikers, fish, and some crabs (not ususally hermits) and shrimp. "Standard" detritivore kits should contain nothing harmful. You can alweays ask the vendor before purchasing one.
Steve
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