I have a white oscar that is about 2 years old. She is probably around 12 inches. About 4 weeks I came home and found her laying on the bottom of the tank, fins barely moving. Next couple days seemed her fins had quite, so I went to get her out of the tank and her fins started moving again. So I let her be and around 3 days later she was back swimming, slowly but a start. A few days later she was back to normal. She is in a 250 gallon tank with a male oscar, a pacu and a gar pike. Approximately a week later she was moving slowly again and the pacu picking at her fins. We took the pacu out (no longer with us)and she was coming around but was swimming pretty much in a circle (think of trying to row a boat with an oar only on one side). Then she seemed to recover from that and slowly back to normal. Then she started having what appears to be balance issues, her nose wants go down and her tail up. She would often get under the figures that are in there, just so she didnt have to fight to keep her tail down. Again she slowly came back a little. Then when we put food in the tank (jumbo feeders)it appears she cannot either open her mouth or has no suction to draw anything in. Felt horrible, she would swim after them but unable to get the food. We tried some small pellets we have to see if she could get them in her mouth, no luck. Now I came home today and she is back to laying flat on bottom, almost appearing lifeless, though you can see her breathing heavily. I read on here how to euthanize them, but I hate to do it, for fear she may recover. Any suggestions on what I can do to help her from what appears to be suffering?

welcome to Oscarfishlover, I am sorry that you have had to come to us under these circumstances. Okay, you've mentioned your fish having balance issues where the nose points down and the tail up. This is actually called head standing. now she is lying flat on the bottom of the tank. I'm afraid this could possibly be a swim bladder problem, the symptoms certainly point to that anyway. I can't think of any other reason why your fish will be behaving like this, I've checked my health book and your description fits the bill.

Normally, these conditions are terminal. However, if you have got quarantine tank, you could try transferring the fish into it and try what is called heat treatment. Heat treatment can be used on conditions such as ick. You want to raise the temperature to around 30°C, fish will actually be okay higher than that but just a little careful. The warmer the water, the more resistance the fish is against infections. Leave it like that for around 2 days and observe the fish. Please don't raise the water anymore than 1°C an hour

If that doesn't work, there are medications that can treat internal organs. One is called Trimethoprim. This is just the name, you should try and get hold of commercially available preparations such as Drylin Eusaprim & borgal solution. I would strongly advise you to seek help from a vet, tell them what is happening, mention these medications and see what he says. I have got to be honest with you, your fish does sound rather ill, where I would really hope it will recover, I very much doubt it will, but i hope I'm proved wrong. But you could try this treatment and see what happens. But please before you do anything based on my instructions, seek a professional opinion first