I am a vermicomposter and a research biologist working on earthworms. We are having trouble with nematodes in our lab-reared earthworms.

Our attempts to get rid of nematodes that are infesting the worm bedding has not worked. They are infecting the earthworm cocoons. Normally, we have been able to decrease them by changing the bedding frequently for a while, then it's fine. I've been trying neem products, but the earthworms do not like it, and the nematodes are still there unless we use levels that also kill the earthworms.

Anyone have a good nematode killing product that doesn't hurt earthworms?