Miscellaneous Freshwater Fishes
If you like large predators then these are the fishes for you. Depending on species they range in size from about 15 cm (6 in) to well over 1 metre (36 in) when full grown. All are predators which feed on live fishes and other live foods, but in the aquarium they can be weaned on to dead fishes such as whitebait, and pieces of fish and meat as well as large earthworms. As with all large predators, feed them only when they are hungry. In young fishes this tends to be almost every day but in adults it may be only once a week – when they will gorge themselves.
Snakeheads have an accessory breathing organ which allows them to live in water with a low oxygen content, and, like some of the labyrinths, they often go “walkabout” in the wild, moving from pond to pond in search of food. Obviously a tight-fitting cover glass is important, held in place by a heavy weight if your fish is big.
In general snakeheads are tolerant of poor water conditions, but this does not mean you can neglect the filtration. They are large predators which produce high protein waste, necessitating a filtration system capable of preventing any build-up of toxins such as ammonia, and regular water changes to minimize nitrates. Snakeheads make longlived hardy pets which will feed from your fingers once they become accustomed to you. The only limiting factor is size, but this is not as much of a problem as you might think. If well fed, they tend to sit around doing nothing, so a large aquarium is wasted on them. Provided the tank is at least twice the length of the adult snakehead and the width at least equal to its adult length, then it will be happy.
They are not fussy when it comes to decor, and although bogwood and plants can be included to create a more natural effect, they adapt well to a bare tank with a gravel substrate. Filtration can be by internal power filter, and while not light-sensitive they do seem to prefer subdued lighting. Temperature can be anywhere between 22-26°C (72- 79°F).
Of those species generally available, the one most often offered for sale is also one of the most unsuitable. Channa micropeltes has the common name of red snakehead because of its coloration when young. Babies (and we do mean babies’) of about 15 cm (6 in) body length have two black stripes running the full length of their reddish body. The red is strongest below the first stripe and is very striking. Unfortunately it fades as the fish grows — as do the black stripes – until you are left with a not particularly attractive, metre-long (36 in), grey and black mottled fish. A much better species to try is Channa orientalis, which grows to only 30 cm (12 in) and, while a drab fish as a youngster, develops a lovely blue sheen to the body and fins as it matures. The fins are edged with bands of black and yellow.
Snakeheads tend to be loners and are usually maintained one to an aquarium. If you have the space you might like to try breeding them. In all species the male cares for the eggs, but some are mouthbrooders, while others guard the eggs which float at the surface under thick plant cover. In the larger species the eggs may number up to 3000, but in the smaller mouthbrooders only about 40 are produced.