Physella acuta, commonly called bladder snails, European physa, and the tadpole snail, is an air-breathing freshwater aquatic snail in the family of Physidae. Bladder snails are native to the Mediterranean, but have become naturalized in many areas of the world. Snails in the Physidae family have sinistral shells, which have large apertures, pointed spires, and no operculums. Physella acuta shells are spotted and somewhat transparent. This species makes exceptional aquarium pets and are great for cleaning algae, dead plant material, leftover food, and various other detritus that accumulate in freshwater aquariums. Some aquarium enthusiasts consider Physella acuta a pest snail because of their ability to reproduce quickly in freshwater. Excess food in aquariums will increase their rate of reproduction. Introduction of predatory snails or the manual thinning of snail populations can be performed to keep populations down if desired. Bladder snails can use air bubbles in their shells to float to the surface and crawl upside-down on the water surface tension as if it were a solid surface, they can also release the bubble of air and sink quickly to the bottom if startled.
