Tokyo-based Genesys World is now selling a small Qulio Fish Tank [Japanese] specifically designed to view and breed Clionidae, a family of small floating sea slugs, also known as sea angels. They are shaped a little like angels, and have flapping "wings".
Breeding of these exquisite Clionidae is difficult, and until now this beautiful sea life could only be seen in special facilities such as aquariums. The Qulio Fish Tank replicates the ocean conditions in which sea angels breed and thrive.