[Federico Sibona]

Tornando un attimo ai Parambassis:

Parambassis lala is often mentioned in aquarium books but is actually quite rare in the hobby. From India, Bangladesh, and Burma. A delightful species; it has a yellow-gold tint, with the males also having a brilliant blue edge to the dorsal and anal fins. These fish get to around 3 cm (1.5 inches) and can be kept in the same way as the common Glassfish Parambassis ranga with which they are sometimes confused. Normally found in streams and ditches, and best kept in soft, slightly acidic water, though will tolerate hard, more alkaline water well.

E per gli Ambassidae in generale:

One of the most widely held myths in the hobby is that Glassfish need brackish water. It is certainly true that there are brackish water Glassfish, and even a few that live in the sea, but none of these are routinely traded as aquarium fish. Most of the species sold to aquarists come from freshwater streams and ditches, while a few come from rivers and blackwater streams. By default, therefore, any Glassfish offered for sale in a tropical fish shop should be thought of simply as a freshwater species and housed accordingly.

[asserzioni di Neale Monks, non proprio l'ultimo arrivato]

PS: ho citato il Parambassis lala perchè i ranga (ed altre specie che talvolta si trovano in commercio) vengono troppo grandi per la tua vasca.