They are extremely peaceful and easy to take care of demanding a tank size of around 40L to meet its needs. They can grow up to around 2 inches. They have very big eyes for their smaller bodies and have an even smaller mouth. They like to hangout in crevices and rocks where they can perch or hide. To keep these fish it is a great idea to have a decent amount of liverock so that they are able to graze on the algae and also be given plenty of places to hide. In smaller tanks they can help keep algae in check, but in larger systems since they are so small they might have a hard time keeping up.