Betta fish may be beautiful creatures, but they don't take care of themselves. Check on your fish regularly, even while it's healthy, and pay special attention to its appearance and body language. Keep your eyes peeled for changes in your fish's appearance. Pay attention to the betta's behavior. Remember the symptoms of various fish diseases. If your fish definitely seems sickly, but possesses no distinctive symptoms, it may be best to take preventative action by administering betta medication like Bettamax. Many medications for treating your betta aren't easily available at the local pet store, and may take several days to ship.