I couldn't resist, I bought a small red tailed shark tonight. He's only about 2 in. now and I put him in my 5 gal minibow with a "black lyretail molly" (that's what the sign said at nnnnnn, now I know it's no molly! not quite sure what it is actually, platy maybe). I'm cycling the tank now for about 2 weeks, daily water change of about 1-1 1/2 gallons. I also add nitromax to help build up the good buggies

. The lady was kinda rough trying to catch him, as I noticed when we got home, his one gill area looked inflamed so I added some mellafix to the tank. I have hiding places for him since they like that. Also a bubble curtain for airation.
He seems hyper, though. Darting up and down the side of the tank, he'll even turn on his side mid-swim. My question, is this the norm for these guys? I can't find anything online that describes behavior, other than they are aggressive to their own kind.