Those are some good looking tanks! I was 100% sure on black substrate for my next tank but your white/black mix has got me thinking...
I am thinking about 125 to 150 gal.
I am either going to do a large shoaling/schooling tank or a dutch aquascape.
Either way I really like the furniture look of your tanks and will be looking for a similar look.
I am also sold on the UV/CO2 loop. If I can keep my fish healthy and my water clear (not scrubbing algae) I am going to be a happy camper.
Thanks for the inspiration!