Lol yeah cause your a pro right? Stating its definitely not a female is a bold guess cause that's obviously just a guess. With the pics he posted nobody can be 100% sure either way. I would argue female due to the lack of spangled in the unpaired fins, the red tones in the body and the dorsal that is 2/3's black, unlike a males which can look all black or barring thru. So yeah until there's clearer pics its an unsexed festae.
pics are not clear but as jason stated and the first thing i noticed is the dorsal. quite a few of my females looked very similar until a male was put in the tank then true color came out. you should vent it so theres no guessing game.