i hope im posting in the right area.. Im sorry if im not.. i have been searching for a month to find out what this fish is.. my wife bought a bunch of feeder goldfish for our oscars and this guy was in the mix... Definately not a feeder fish.. im guessing some type of cichlid due to the fin structure but other than that im clueless our local tropical fish store says they dont recognize it as a common cichlid.. 
