No problem, ya which ever one grows the fastest he would more then likely try to eat the smaller one, and if he cant get him down the hatch he would seriously hurt the smaller. Or if the smaller one was to big to swallow the bigger guy may not be able to release him because of there 2 big teeth in the front of there mouth and he could choke, resulting in losing both frogs maybe. And ya the 10 would house the 2 right now at that size if you split it. After a few months when they get abit bigger you could put them in there own 10s and if they are both male if you place things properly and don't over crowd the tank some people will house them in the 10 there whole life. When full adults the biggest most people go is about a 20 gallon for one, and if its a cranwelli you probably really don't really need that, I would put a full grown C. ornata in a 20.