Detailed explanation of fish medication methods

Splash method:

The splash method, also called the broadcast method, is the most commonly used method when using medication to prevent and treat fish diseases. Drugs that kill certain pathogens but are harmless to the fish themselves are broadcast throughout the fish pond to reach a certain concentration, so as to kill pathogens on the fish's body surface and gills as well as in the water, thereby curing or improving the condition.

When using the splash method, you must first correctly measure the area and water depth of the fish pond, calculate the volume of pond water, then calculate the dosage, and evenly splash the drug into the fish pond in a certain manner. It is easy to master. However, for larger water bodies, this method requires a large dosage and a lot of labor,

causing certain difficulties. At the same time, people and livestock have more opportunities to come into contact with the drug.

Immersion method

The immersion method, also called the dip method, is to prepare a relatively high drug concentration in a certain container and force the fish to receive the drug for a shorter time, thereby killing pathogens on the fish's body surface or gills. The immersion method is usually used before and after transferring fish fry to another pond or during transport. For some pathogens that require a relatively high drug concentration to kill, this method should especially be used.

When using the dip method, different operating methods are used depending on the container. There are roughly two types of commonly used containers. One is a fixed container, such as a basin, bucket, fishing boat, box, canvas basket, etc. The volume of this type of container is fixed. After calculating the water volume in the container, add the required dosage at one time, then put the fish in and immerse them for a certain period of time. If multiple immersions are needed, then after each immersion, add the drug in increments to maintain the effective concentration. The other type is a slightly flowing-water container, usually a fine-mesh cage. According to the number of fish, the water volume can be flexibly calculated, the required dosage added, the required concentration reached, and the fish put in for immersion. Because the medicated liquid in the cage continuously seeps outward and is diluted, the drug must be replenished at any time during the immersion process.

The length of immersion time is mainly determined by the fish's tolerance to the drug. Within the safe range, the longer the better in general.

The advantage of this method is that it enables the fish to undergo treatment with a high-concentration medicated liquid in a short time, and its effect is relatively strong; the container volume is relatively small, which can save on the amount of drug. However, during operation, because containers differ, water temperature, dissolved oxygen, the fish's physical strength and other factors vary greatly, and if not handled properly, accidents are likely to occur. Moreover, this method is limited to killing diseases and pests on the fish body, and the fish after immersion can still be infected when returned to the pond. In addition, because the fish are relatively crowded during immersion, the fish are easily injured.