Obviously named for its translucent flesh, the glassfish is an interesting, slightly odd addition to the right aquarium. They are a schooling fish, and prefer to be kept in groups of five or more. They can be kept in smaller numbers, but they will be shy and will spend much of their time hiding. Even when kept in larger numbers, they tend to not be aggressive, though they can get to be very bold and energetic.

Glassfish have a reputation for being difficult to keep alive, but this belief largely stems from the myth that they require brackish water to survive. In nature, these fish live in standing water such as bodies created from dammed mountain streams, not estuaries or other areas of brackish water. If they are kept in true freshwater, they seem to be fairly hardy fish, no more difficult to keep than many tetras.

I am currently unaware of the difficulty of breeding glassfish in the aquarium. In the wild, they breed prolifically during the rainy season. If the tank's water temperature is raised to 85° and the fish are fed a healthy diet of high protein food, they may be induced to breed in an aquarium.

One particular note about glassfish is that, due to their transparent flesh, they are often injected with fluorescent dye. The result is a glassfish with fluorescent dots floating in its body. Most of these fish do not survive the dyeing process, and those that do are four times as likely to develop certain viral infections as undyed glassfish. For more information on this, check out the article on dyed fish.