I can post a pic this weekend, when I go back to the tank. It is about 2 hours away at the moment. It seems to do it when the lights are on and the mucus seems to be coming from under the mantle folds. It seems to do it when the lights are on. When I was at the LFS they had some croceas doing it there are as well and they said it is normal. I have had this clam for almost 2 yrs now. Since I have owned it, it has excreted such mucus in the past, but not for such extended ammount of time. Other than that,it looks as healthy as can be. Great Extension, colrs are bright and vibrant, and I can notice shell growth.