Fish Sick From Melafix?

[BeccaAmes]

Hi, I recently made a thread in this board about my goldfish's fin rot: http/www.fishforums.net/index.php?/topic/414218-fin-rot-medicine/
 
I just put in the melafix and at first he seemed to be fine, but it wasn't long before he floated down to the bottom of the tank and stayed there. I've never seen him do this before, and he's alive (I can see his eyes moving) but he doesn't seem to be breathing well. Once in a while he will stir and his gills will move but other than that, nothing. Is this a side affect of melafix? I made sure I didn't overdose on the medicine, followed the directions, etc., but I don't know what caused this. Does anyone know what might be wrong?

 

[techen]

Check water stats and post them here?
 
I doubt very much it's Melafix as it's a recommended product for issues such as fin rot.

 

[BeccaAmes]

Thank you for replying! He's been swimming more as I've checked on him but then goes back down to rest at the bottom. I fed him a little while ago and he perked right up but he's resting again now. Could this be swim bladder disorder? Employee said I should hold off on feeding him for a couple of days, then feed him skinned peas.