Everyone tries their hand at keeping Betta splendens (Siamese fighter) at some time in their aquatic career. Although they are often kept in community aquaria, this is not the right place for them, particularly not for the males.
Two species of cichlid are found almost exclusively in brackish water: Etroplus suratensis (Green chromide, 45 cm (18 in)) and Etroplus maculatus (Orange chromide, 10 cm (4 in)). Both occur in coastal regions of southern India and Sri Lanka, chiefly in brackish estuaries and lagoons. The salinity of both types of habitat is variable, depending on the state of the tide and the fresh water input, which varies with the seasons.
Now for something a lot smaller. Brachygobius (Bumblebee gobies) are suitable for those of you who cannot keep a large brackish water aquarium, because they will be quite happy in a 60 x 30 x 30 cm (24 x 12 x 12 in) tank. Although these fishes are small, we do not recommend using anything smaller than this because it is more difficult to maintain good water conditions in a small body of water.
Remarkably few European native fishes are kept by aquarists and yet some meet all the criteria of a good aquarium fish, that is, small size, pretty colours, and interesting behaviour. The sticklebacks meet all these criteria in full and yet are very rarely even thought of when choosing aquarium fishes.
The halfbeaks occur in southeast Asia and are found in both fresh and brackish environments. Most of those available in aquatic outlets have been acclimatized to freshwater conditions (with maybe a level teaspoonful of salt per 4.5 litres/1 gallon), so you should have no problems with them
As suggested by the common name, the Chandidae (Glassfishes) have transparent bodies which allow you to see the skeleton and many of their internal organs. Two species crop up every now and again in the trade: Chanda ranga (Indian glassfish) and Chanda wolffii. The larger of the two is C. wolffii at 20 cm (8 in) although it is most unusual for them to reach this size in captivity even if they are fed correctly.
In the tropical waters of Africa we find a very interesting family of fishes, the Polypteridae (Bichirs, Reedfishes, or Lobe-finned pike). They have elongated, snake-like bodies which are covered with enamelled, diamond-shaped (ganoid) scales.
Many gobies are brackish water fishes but there are some that are at home in fresh water. Most are bottom-dwellers, lurking among stones and roots, and scuttling from place to place in search of food.
The African anabantids belong to the genus Ctenopoma and although they are usually referred to by their generic name, they are also known as bush fishes or even climbing perch. To avoid such confusion here, we’ll stick to Ctenopoma (Bush fish).
