If the unfinished tail of tropical fish is changed properly, the water temperature should be raised at the same time, and a little salt should be added. If it does not recover, it can be soaked with yellow powder. Unfinished tail is a common disease, which is caused by two reasons, one is infected with the disease, and the other is stimulated. The former is troublesome to treat, but the latter can recover by itself as long as the water is raised well, without extra medication.

1. Water quality deteriorates: Fish have unfinished tail, which is usually related to water quality. Long-term failure to change water will lead to the deterioration of water environment, thus affecting the health of fish. Therefore, it is necessary to change every once in a while. Every time you change water, you don't need to change too much. It is enough to change a quarter or a fifth, and it is not good to change too much.

2. Infected bacteria: When fish are infected with bacteria, they will also have unfinished tails. In addition to unfinished business, there are other performances, such as rubbing and lying on the cylinder. If you want treatment, you need to sterilize in time to avoid aggravation. Sterilization usually requires some sterilization drugs, and the dosage of drugs needs to be strictly controlled, otherwise phytotoxicity will occur.

3. Sudden temperature change: When the temperature changes suddenly, the fish will also be stimulated, resulting in stress response, and the tail may rot. In view of this situation, the best way is to keep a constant temperature. Heating rods can be placed in the fish tank to control the temperature and avoid too much change in temperature.