Well this morning the urchin, fish and coral all appear to be doing fine! I'm so glad! yes, it apeared to be releasing it from the outward back side where the waste is also released. In your class, what did the fluid look like? Your theory sounds good to me! I need to do some more research. Know of any good articles on this topic on the web? Thanks so much for your response, I guess everyone else was sleeping while I was having a panic attack over my urchin!