A while back, I found a new type of snail in my tank. The one on the left I originally identified as a common pond snail based on Internet photos, but a month or so ago I found the snail on the right in one of my tanks. He is slightly larger, faster growing, and faster in speed of movement than the snail on the left. The snail on the right is also darker (almost black bodied with a dark brown shell) and has sharper more angular features. I have no reason to believe either is harmful as both are aquatic snails that eat algae and waste breaking it down for my plants. Based on photos and descriptions, can anyone give me a more specific ID than pond snails?
