Whether guppies need oxygen depends on the breeding environment and the number of guppies. Although they belong to tropical fish, their demand for oxygen is still relatively low compared with other tropical fish.

If the density of the fish is normal and a filter is installed in the fish tank, the breeder does not need to deliberately oxygenate them. Because filters can also increase oxygen in water, the amount of dissolved oxygen in water is enough for them to absorb, so there is no need for oxygen.

If they are raised at a high density and without a filter, the breeder needs to give them oxygen. Because the density is too high, their demand for oxygen will increase, and the dissolved oxygen in water cannot meet their demand, so extra oxygen is needed.

Guppies die when they are deprived of oxygen, because they mainly rely on gills to absorb oxygen from water. If the oxygen content in the water can't meet their needs, they will die.

However, the demand for oxygen for guppies is not very high. Breeders can ensure that their oxygen is sufficient as long as the feeding density is normal and the water is changed regularly. If the guppy is deprived of oxygen, the breeder need not worry, just turn on the oxygen pump and increase the dissolved oxygen in the water.