What should I do if my betta died suddenly?

If your betta fish has died suddenly, it is important to remove the fish from the tank and properly dispose of it. Then, you should check the water quality in the tank to ensure it is suitable for fish. It may be helpful to do a partial water change and clean the tank to prevent any potential issues that may have caused the sudden death of your betta. Additionally, consider consulting with a veterinarian or a fish expert to determine the cause of death and prevent it from happening again in the future.