The order for male+female pair gave me two very nice males. When put together, one killed the other in a couple days. I have obtained two for sure females now so when added to the aggressive male tank, I had to remove him to a 55 gallon community tank as he started chasing the two females and they were not cheap. Live and learn. All Cardinals, Corys and Ottos are doing great.
These guys are super cool, healthy, energetic, and hungry. They did hide for the first few days but then just when I was wondering if they were even still in there I see them popping out everywhere.