Color is not a great way of telling gender. Does he have eggspots? Longer fins? These can indicate male as well. The best way to know for sure is the vent him.I GOT HIM AT CHRISTMAS TIME, HE IS ONLY MAYBE 2-2.5 INCHES. THE DEALER SAID TO WAIT UNTIL HE IS AT 3INCHES. BUT I AM PISSED CUZ I REALLY WANTED A MALE!
http://www.fishhead.com/articles/ventsex.htm