Please can someone help, my fully grown convict started acting strangly a week or two ago. He looked as though his head was heavy and was placing it on the bottom of the tank, now he is totally vertical in the tank, head down. I have also just noticed that some of his scales seem to be sticking out along his underside. I was advised to use revitaliser tonic, however this has made no difference. I would realy like to try and save this fish if it is possible. Any help gratefully received