Sorry, let me re-phrase. I think that not mixing your stock is a "newbie mistake."
No offense intended. Good luck with your KKs--hopefully you can prove me wrong ;-)
The tank is mostly about aesthetics for me. I just love the way the BKK look. I’m not looking to be a power breeder (though of course it would be nice to establish a breeding population). If I fail, well, I can decide in six months or a year to add CBS to the tank.
Actually it's really common to see the shrimp pooping in photos, some shrimpers do it on purpose, because if the shrimp are eating and pooping, that means they are healthy and unstressed. I think it's weird too but it makes sense if you're trying to sell them.