1. Quarantine the fish. This will prevent the spread of disease to other fish in your tank.
2. Observe the fish closely. Look for any changes in behavior, appearance, or appetite.
3. Test the water quality. Make sure the water temperature, pH, and ammonia levels are within the ideal range for betta fish.
4. Treat the fish with medication. There are a variety of over-the-counter medications available for betta fish. Be sure to read the instructions carefully before using any medication.
5. Provide the fish with a healthy diet. A healthy diet will help the fish to stay strong and resistant to disease.
6. Keep the tank clean. This will help to reduce the risk of infection.
7. Avoid stress. Stress can make fish more susceptible to disease.
If you are not sure what is wrong with your betta fish, you can take it to a veterinarian or pet store for diagnosis and treatment.
Here are some specific signs of illness to look for in betta fish:
* Lethargy: Betta fish that are sick may be less active than usual. They may spend more time lying on the bottom of the tank or hiding in plants.
* Loss of appetite: Betta fish that are sick may not eat as much as usual. They may also spit out food or have difficulty swallowing.
* Frayed fins: Frayed fins are a common sign of illness in betta fish. They can be caused by a variety of factors, including bacterial infections, water quality problems, or physical injury.
* Fin rot: Fin rot is a bacterial infection that can cause the fins of betta fish to become red, swollen, and disintegrate.
* Dropsy: Dropsy is a condition that causes betta fish to bloat up with water. It can be caused by a variety of factors, including bacterial infections, kidney disease, and liver disease.
* Ich: Ich is a parasitic infection that can cause betta fish to develop small, white spots on their bodies.
If you see any of these signs of illness in your betta fish, it is important to take action immediately. The sooner you start treatment, the better the chances of your fish recovering.