I know you're excited and have a hard time resisting as I have the same problem. I've learned the hard way and lost tons of money/animals so now I"m super careful and research every single thing before I buy it and make sure it's healthy and eating before I get it. Okay sorry I'll get off my soapbox, just thought I'd share my story, there's nothing worse than being so excited about a new critter and haveing it die loosing money and the cool animal.
Anyway, my 2 clowns were tank raised and ate at my LFS
, however they didn't eat for close to 10 days once I got them home. I was getting really worried then all of a sudden they started pigging out
I wouldn't worry too much yet.