I was looking at my tank earlier just looking in the rocks and watching the little life around.I been observing how the rocks look nice and clean lately..I knew I had one or two but I look around and I have stomatellas all different sizes through the tank,so I watched them..The small ones clean the sides and inbetween polyp stems on frag plugs,and the zoas dont even flinch.. then I see one nice size one it ate a small clump of gha in a crack of a rock the clump was the size of a quarter and this thing ate it in like 3 minutes.The snails are around slowly munchin but these things devoured algae in no time..They are doing a great job for something I didnt have to buy and add..Its pretty cool seeing all these little things doing their thing when you look close..there must be so many things we dont even notice.