We just got a mystery snail and I am struggling with how to feed him. He is in a 37 gallon tank with two goldfish who don't seem to give him much trouble (the bigger one sometimes pecks at his shell but not frequently enough to be an issue). My question is how I can feed him without the faster, piggier goldies snatching his food first? I just did a water change, and tried putting him in a bowl with some romaine and spinach for a while. He doesn't seem to be eating, though, and I'm afraid to keep him out of the tank for too long. I am having trouble keeping the veggies on the bottom of the bowl for him. Also, I read I can put egg shells in my filter to help with his shell. Does that work?