Not all fish need to be oxygenated all the time, but it is always good to be oxygenated all the time. Fish live in water and breathe in it at the same time, so the oxygen content is very important. If the dissolved oxygen is too low, the fish may feel uncomfortable and even float. If the breeding density of small fish is not high, you don't need to be oxygenated all the time, but the big fish can't, and it may be affected if you stop for a while.

1. Koi: Koi is an active fish. Because of its vigorous vitality, it has a great demand for oxygen, so it needs to be oxygenated, otherwise it is easy to die of lack of oxygen. There are many varieties of this kind of fish, but they are mild by nature, easy to raise, and the requirements for water temperature are not high.

2. Arowana: As a common large ornamental fish, Arowana consumes a lot of oxygen, so it can't be raised without paying attention to oxygen. The body length of this kind of fish is about 40-50 cm, so it needs a bigger fish tank to raise it. Because of its fierce temperament, it is difficult to mix it.

3. Siraitia grosvenorii: Siraitia grosvenorii also prefers high dissolved oxygen environment. If dissolved oxygen is low, it is often difficult to feed. Usually, the water temperature should be kept at about 30 ℃, and the dissolved oxygen should be greater than 6 mg per liter. If the oxygen is insufficient, it needs to be oxygenated by oxygenation equipment.