A to the hobby not so well known family are the Clingfishes (Gobiesocidae). Recently there are about 155 known species. From Australia alone 20 new species have been described in the last few yeas. Clingfishes are small fishes mainly from tropical seas. There are only 6 freshwater species. Most species are between 4 - 8 cm large. Their most important characeristic is a ventral suction cup which allows them to stick onto varios substrates. Other very important characteristics of the family is their shedless slimy skin and their unparted fin.