My son's fish Rock N Roll has been in 3 tsp/G epsom for 13 days now (starting tomorrow the plan is to taper down). After the past 3 days of 50% water changes, he had been doing great. Today I did 100% water change and shortly after noticed that he was "snapping" at something on the surface of the water, as if he was eating, but I hadn't fed him anything since the water change. When I looked closely I saw that there were some little translucent flaky things floating in the water so I did another 100% water change, this time thoroughly scrubbing and rinsing the tank in the process. Now he is super-buoyant all of a sudden - he literally can't swim downward at all - and I'm wondering if it's possible there was some salt residue on the bottom of the tank and I stirred it up during the water change and that's what he was eating? If this is the case, is there anything I should do to help get it out of his system? I think this may have actually happened before, but I didn't realize what was going on and by the next day he was pretty much back to normal but I'm still concerned that he may have eaten a lot of salt residue and how that might impact him. TIA!