When the water is seriously deteriorated, harmful substances such as ammonia nitrogen and hydrogen sulfide are most likely to be produced. Hydrogen sulfide has a strong pungent smell after it is seriously produced.

The most obvious symptom is that its taste is similar to that of rotten preserved egg. Any pond with odor indicates that the water body has deteriorated to the extreme, and measures must be taken immediately to improve the water quality, otherwise, the consequences will be unimaginable.

The production of everything has a certain causal relationship. Ammonia nitrogen, nitrite and hydrogen sulfide are all produced when the pool water is poor.

However, it must be accompanied by the lack of oxygen in the pool water. It is a toxic substance that is very harmful to fish. It will decline if it does not die.

Therefore, when adopting various measures (applying improver, filling and changing water, etc.) to improve the water quality, it is necessary to first open the aerator and take "surgical" emergency measures to rapidly increase the dissolved oxygen in the water, which will get twice the result with half the effort.

At ordinary times, if the dissolved oxygen in the water is insufficient (low dissolved oxygen) for a long time, the process of water deterioration will be accelerated. On the contrary, as long as the dissolved oxygen in the water is moderate or sufficient for a long time.

Generally, the water body will not or at least not be easy to deteriorate, so sometimes some ponds have black water (like water).

However, fish are normal, mostly due to moderate dissolved oxygen or low density of fish. Therefore, maintaining sufficient dissolved oxygen in the water is the key to prevent the occurrence of toxic substances in the water.

At ordinary times, some fish farmers are eager to spend money to buy such bottom modifiers as water regulating agents and so on after they neglect the "oxygenation" work, resulting in the deterioration of the water body.

As everyone knows, if the dissolved oxygen in the water itself is insufficient, the vast majority of these water regulators or bottom modifiers will have no effect after they are poured into the fish pond.

It's a waste of the money and has no effect, because most of the these "drugs" regulating water quality are microbial agents.

Microorganism itself is also a "living body", and it also depends on appropriate oxygen to supply its own vitality, and then it will "operate". That is the truth.

In short, "dissolved oxygen" in aquaculture is the top priority of all work, and it is the primary work more important than anything else.

Dissolved oxygen in water is not only the most basic material condition for fish life, but also has the function of "detoxifying" toxic substances in water.

Changing water, adding water or turning on the roots blower at ordinary times is the king way of fish culture.