The yellow powder is nitrofurazone, which is often used to treat skin rot, bacterial gill rot, erythroderma, bacterial infectious vertical scale disease, fin rot, skin inflammation and congestion, chickenpox, cave disease, baldness and white mouth disease, etc.
In the process of drug use, the dissolved oxygen content in water will decrease, and the oxygen exchange ability of fish gills will be inhibited at the same time. Therefore, oxygen must be added in the application process, but generally air is blown by air pump and three-in-one water pump, and oxygen is not needed at all. Oxygenation is usually only used for the transportation of live fish.