Arowana can't be raised in a 40 cm wide fish tank, because Arowana is relatively large in size, and the body length of Arowana grown in the wild can reach about 100 cm in adulthood, and even artificially raised Arowana can reach about 50-60 cm in adulthood. If they are kept in a 40 cm wide fish tank, it will be difficult for them to turn around. In addition, the bones of Arowana are relatively hard, so the body can't bend when turning, and the bones may deform after a long time. Therefore, under normal circumstances, it is best not to use a 40 cm wide fish tank to breed Arowana. If it is a juvenile Arowana, it can be raised for a short time, and it should be replaced in time after they get bigger.

Arowana belongs to large fish, and the length of Arowana grown in the wild can reach about 100 cm. Breeders should at least prepare a fish tank with a length of 120 cm, a width of 60 cm and a width of 70 cm for them, so that they can move normally. If you want them to grow bigger, you should prepare a fish tank with a length of 200 cm, a width of 80 cm and a height of 80 cm.

Arowana is irascible and fierce, so it is best to keep it separately to avoid fighting and injury. If you want to mix, you can choose some fish with mild personality, similar size and habits.