Trigger can't seem to stay down.

[Doubledown]

I have Crosshatch Trigger that has been with me for nearly 3 months. I noticed today thet he has abrassions on his chin and top of his nose. He is swimming strangly - more tail swaying than before and shifting from side to side.

He appears to be having trouble with bouyancy. His tail seems to want to float.

Has anyone seen this and what can I do to help/treat him?

Thanks
Chris