Its really difficult to determine gender of almost any variety of Texas Cichlid until they reach maturity. My Red Texas is less than a year old and is getting big, nearly nine inches. At about three inches it was obvious that the RT was not going to be a community fish. I assumed he was a male due to the "Extreme" aggression. His nuchal hump became noticable at about the six inch mark. Judging by the shape of your Red Texas, I'm guessing male. Females tend to have a more bullet shape. Hope your plan works out.