I have a T-Derosa clam. He has been doing very well until the last couple of days. I had moved his spot in the aquarium to a new area, close to an anemone. The tentacles from the anemone was touching the mantle yesterday i notice, but the clam was still doing fine and seem not to be bothered by it.. This morning, i notices the tentacles touching once again, this time the portion of the mantle touched by the anenome is retracted. I moved the clam to a new location away from the anemone but that part of the mantle is still retracted. I also noticed some type of weird gray slug crawling on the shell that I removed. I have noticed that at night many of the slug type creatures come out and go on my glass. Will the clam be allright?