They already live together if that makes any difference? They're probably even smaller than that to be honest.
Also, will captive bred clowns host any anemone or do the different species like specific ones?
The anemone hosts, the clownfish associate (think hotel (anemone) hosting guests (clownfish)). A group of juvenile clownfish in a breeders tank is not "living together". Once they start to sexually differentiate, the rules of coexistence change dramatically. However, we are way off topic here. Start your own thread in the clownfish forum.