I had a similar problem when i bought a leather frag from my lfs, hidden under the cracks and crevices of that frag were sundail snails i went into panic mode and began to siphon them out with a turkey baster which got all of them out, but in your case it could work but they could be deep into your rock work or other places that might be hard to get to, luckly for me they all stayed on that one rock.