i had an iridescent shark that did that many years ago, he was a good 11 inches or so, he freaked out one day as they usually do and ran right into the heater and broke it.

i did not realize till the next day when i saw almost all his skin gone. do not know if he was electrocuted, tore up from the glass or the chemicals in the heater but he did die a few days later. even after meds.
i wish i could tell you the exact reason but i really do not know. noone had a great answer for me either, i called pet shops, vets etc. and no-one seemed to know. :-?
you could try to call the company to see if there is anything dangerous in there? just a thought! :idea:
(probably for the injury though) but what was recommended for me was to do 30-40% water change daily for 3-6 days. add meds for his skin. but that didnt help me. he was to far too injured.
hope yer fishy turns out a-o.k.! :fish: