This week’s Fish of the Week is one of the most suitable species of its family to keep in the home aquarium and brings with it real character. The rainbow snakehead (Channa bleheri) is a brightly coloured, dwarf species of snakehead with a maximum adult size of 16-18cm.
The family it belongs to, Channidae, contains approximately 50 species, with more discovered all the time! They span across Asia and a smaller group, Parachanna, are found in Africa. Snakeheads vary greatly in size, with the rainbow snakehead being one of the smallest, whilst the largest can reach over 100cm. This would make those species (C. micropeltes, C. marulius, C. argus for example) wholly unsuitable for life in a home aquarium.
Snakeheads have fantastic adaptations that have allowed them to conquer many different habitats. Their strong pectoral fins and muscular body allows them to move across marshy land. They have a labyrinth organ, a kind of primitive lung that is adapted from a highly vascularised part of the gills. This allows them to absorb oxygen from the atmospheric air. Being able to breath air helps to extend their journeys across land and live in anoxic bodies of water, that most fish could not survive. The labyrinth organ is a shared adaptation within the order Anabantiformes. This group includes the popular aquarium fish gouramies and the siamese fighting fish Betta splendens. These adaptations have allowed snakeheads to impact non-native habitats where they were kept as pets (USA, for example). They quickly began to impact the native fauna and were classified as an alien invasive species and banned. In the UK, the northern snakehead C. argus, is banned as it can tolerate cooler water. In Scotland, all species of snakehead require a licence to be kept as pets.
The rainbow snakehead is best kept with others of its own kind. Some fishkeepers have had success maintaining them alongside robust fish that are not too small to be eaten. They are predatory and their diet should match this - frozen meaty foods (don’t expect them to take dry foods).