Im still waiting on mine to fully color as well.. i have a group of 9 in a 90gallon around 3".. you can sex them but no color yet.. the male i have in a all male tank has lots of blue just no blaze. So i believe the blaze comes last not first.. Of course a few things will factor into what size they will color at. Tank mates, Tank size, water conditions, Diet, Lighting, genes, and overall health.