Thanks for the comments. hoping the marbles to at least improve their looks close to how they look in the past in the white based tanks. made a mistake thinking light blue suited them, but some how the fish saw it as dark environment and blended in. now at least the males started to improve their base colors. hoping the female will follow suite. i gave away the marblexpearl male as he is too agressive. killed 15 inch red arowana and 17 inches tor tambroides. and in my friend tank, he killed 18 inches koi. now in solitary tank with only 18 inch arowana patroling the top half of the tank at another friend place..