The color is looking good on your fish! Vast improvement. It really depends on genes, but it looks as though yours has some good genes! Clean water and quality food is the biggest factor after genes. I also use the mirror trick and teach them to chase fingers. It helps with dominance. I also see a boost in kok size by fasting him once or twice a week while pumping the other days! Try it! Don't feed him for a whole day then look how much his kok is popping the next! It works! Fasting also really brings out aggression!
