Will they bother anything in my tank such as a clam or coral?Yup, drop me a PM if you're interested in picking some up this weekend or Monday I may be around. Basically I throw out a decent sized ball every few weeks, so just depends on when it was last cleaned.
Full Disclosure, I have pods in them, but also Asterina starfish and fireworms possibly (You can probably clean those out by hand) but no known diseases and I quarantine all fish and coral rigorously.