Ouch, you drove an hour to get a small powder brown and the guy couldn't get it out of his tank?!? I would have helped him take rock out untill that butthead was netted and in my bucket, but thats just me.
I have a 3" powder brown in a 6' tank with a 4" yellow tang and the yellow beats the beans out of the powder. luckily the brown it fat and healthy and seems quite hardy and able to hold his own. I bought a sickly powder blue a couple months ago and my yellow tang killed him in 2 days, but he was really skinny and I honestly shouldn't have bought it in the first place.
~Will.