I have raised many stains umbee from fry. Rio mag, ultimate blues, and different collection points, I have found the juvies with black pectoral fins and/or black on half dorsal turn out to be female. I was raising a few hundred gorrilus black fry in a 60gal and they were fine. Then I transferred them to a 5foot tank and maintained water changes at least 3 times a week. I noticed one was growing faster than the others. Then I noticed the bigger one was eating the others. I gave as many away as possible. I put ads on Craigslist and talked to fish store but at least 100 were remaining and every day the biggest fry would eat 3,4,5 or more. Now I have one and assumed it was male until I saw it with jet black pectoral and dorsal fin. So my question is for the experts...does that test hold true 100% on gorrilus as well? Thanks for any input
