if you're having the tanks with a bare bottom you really don't need a clean up crew besides a sponge and a syphon tube. :) your fish still look rather small. do you know hold old they are? It can take upwards to 3 years before a pair will form and become mature enough to breed. my pair of snowcassos are 2 years old and are just barely showing signs of breeding.
Visit MBI - Marine Breeding Initiative to get all the information you need such as breeding, food culturing, and system builds to help you get started.
your fish have awesome markings.