The shark disappeared a few days into quarantine. Simply melted away. The other fishes in the same tank made it though.
They came in with 2 a bit sluggish. Then later one seemed to die i held him in my hand and didn't move but I put him back in the tank and the next morning the 2 were back all perky. Im glad I didn't take addictive and toss him, lol. Any ways 2 weeks in and they're doing well