Crushed coral to seed new sandbed?

Hey all, I recently set up a new 29G reef tank with a sandbed. The tanks been running for about a week now, and I read that it would be beneficial to put a raw shrimp in the tank to help start the cycle. (I've never heard of it, so its all new to me). Anyways, I decided to try it and the shrimp has started to "grow" what looks like a spiderweb. I assume this is a fungus and that I should remove the shrimp? Also, is there anything not beneficial about seeding the tank with crushed coral from my existing reef to jump start the cycle? I should be fine doing that, right? If it matters I'm doing a fishless cycle on the tank. Thanks