sick porcupine puffer

[sherman]

I recently purchased a 3-4 inch porcupine puffer. He seemed to be eating well but I noticed he stopped eating for the past two three days and then this morning I could see he was having trouble swimming normally and now he's almost completley on his back.

any suggestions?

(technical question - I posted this question in this forum and the Fish Only forum, any way to post it once but in two forums?)