You’re looking at a fish that needs 150 gallons bare minimum to itself, it can easily get 14+ inches. Even my 9 inch Jack Dempsey uses every inch of a 6 foot 125. It used to be in a 55 gallon (4 foot tank), and the difference was night and day when it moved.
At this size you wouldn’t be able to tell it’s a male or female, that really doesn’t show till about 6 inches or so.