Dissolved Oxygen, an important criterion for good or bad water quality in Koi ponds

Dissolved Oxygen, an important criterion for good or bad water quality in Koi ponds

The amount of dissolved oxygen in the water is an important indicator of good or bad water quality, which directly affects the healthy growth of fish. Fish breathe oxygen through gills to maintain respiration and metabolism, once the dissolved oxygen is insufficient, it is very easy to affect the normal physiological activities of the fish, and in serious cases, it will even threaten the life of the fish. At the same time, harmful substances will also increase dramatically in low dissolved oxygen water, causing fish diseases.

Generally, midnight or dawn is the time when the dissolved oxygen in the water is low. When the dissolved oxygen is lower than 5mg/L, the fish will have shortness of breath and floating head. Some data show that the content of carbon dioxide in water is more than 70 times of that in air, while the content of oxygen in air is 20-30 times of that in water. Only through gas exchange can the oxygen in the air be brought into the water, while releasing carbon dioxide. So what can be done to increase the amount of dissolved oxygen in the water?

(1) Non-closed filtration systems

Side filtration, bottom filtration, top filtration, etc. can be exposed to the air, through the cycle of oxygen into the fish pool, which is to increase the process of dissolved nutrients, if the density of feeding in the pool is too large, you can add more air pumps for oxygenation.

(2) Closed filtration system

With a filtration system such as a bucket, the water in the bucket must have limited contact with the air, and the filtration is also closed, so the only way to raise dissolved oxygen is by adding an air pump.

(3) Water changes may not necessarily increase the amount of dissolved oxygen

You must trap the water before changing it. In the process of water trapping, not only the chlorine gas is volatilized, but also part of the oxygen in the water. And the water in the fish pond under normal circumstances, the dissolved oxygen must be higher than the dissolved oxygen of the water that has just been trapped. Therefore, changing the water does not necessarily solve the problem of the lack of dissolved oxygen, oxygenation is the key.

(4) Relationship between dissolved oxygen and the environment

When the power goes out, the first thing to do is to stop feeding in order to minimize oxygen consumption. If it is in winter, with the lower temperature that the fish can only tolerate as the bottom line, there is no need to rush to use other ways to quickly warm up; on the contrary, if it is a power outage in the summer, to use some methods to lower the water temperature, so it is recommended to have a small oxygen pump at home.

(5) Relationship between filter material and dissolved oxygen level

Increase the porous filter media, conducive to the cultivation of nitrifying bacteria, because the increase in the area of water can increase the amount of dissolved oxygen in the water.

(6) Regular operation to reduce fish pond dissolved nutrient depletion

Feeding at regular intervals, less food and more meals, in order to reduce the production of carbon dioxide and harmful substances; timely treatment of food residues and feces at the bottom of the pool, regular water changes, can directly reduce the ammonia, nitrite and other harmful substances, and thus reduce the consumption of dissolved oxygen.