If you think your Oscar may be stressed, there are a few things you can look for. First, check to see if it is hiding more than usual. If your fish is normally out and about but suddenly starts staying hidden, this could be a sign of stress. You should also look for any changes in color or appearance. An unhealthy fish will often have faded colors or patches on its body. Finally, watch for changes in behavior, such as listlessness or aggression. If your Oscar seems unusually lethargic or starts attacking other fish, this could be a sign that something is wrong.
If you notice any of these signs, it's important to take action quickly. Stress can lead to serious health problems in fish, so it's important to do what you can to reduce your Oscar's stress levels. One way to do this is by providing plenty of hiding places in the tank. This will give your fish a place to go when it feels overwhelmed or threatened. You should also make sure the tank is properly filtered and maintained; dirty water can cause stress in fish. Finally, try to avoid overfeeding; too much food can lead to obesity and other health problems down the road