From Dr. Ron Shimek
"Collonista are "mini-Turbo snails." They are seldom purchased by hobbyists, but are relatively common in reef tanks anyway, because they appear to hitchhike in on live rock or in some live sand. When hobbyists first see them, they presume them to be "baby" grazers of some sort. Instead, they have some of these animals. They reach a maximum adult size of about 1/4th inch (6 mm) in height and diameter. They are often tan to white and have mottled brown color patterns on the shell. They can be distinguished from all other Trochoideans by their small size and the presence of a small pit or hole in the center of the calcareous operculum that plugs the aperture. They reproduce well in aquaria, and are quite good grazers. If present in large numbers, they may effectively replace all other grazers in our systems."
