Finrot?

[Radiance]

2 of my paroon sharks' pectoral fins have been reduced to nothing but bone and pink flesh OVERNIGHT! is this fin rot?! or is someone preying on their fins?

tankmates are Common pleco,albino cory catfishes, tinfoil barbs, and bala sharks.

[Morainy]

I have no idea at all. If it's bacterial, then it's super aggressive. Usually, you'd see streaking or something first. I'd probably guess that they've been bitten, but two at once in the same place? There's something very strange!

I hope your fish recover and that somebody with a clue gives you an answer. I've never had this kind of fish...

[Radiance]

culprit found!

my 8 tinfoils are viciously attacking them O_O
chasing them down in a pack and chowing down on their fins
man and i thought tinfoils are peaceful!!

[Tazzy_toon]

I was going to suggest it was the tinfoil barbs, my daughter had some in her tank and they hunted the oscar so much it finally got overly stressed and died. they are nasty buggers sometimes.