Communicating with sister clans?

Recently our clan Judgement Light has grown and decided that to filter our recruits and have a place for more inactive players we would start another clan Jmtl Family. Right now it's managed by one of our Co-Leaders on a second account but up to this point the clans haven't interacted in any way. I'd like for our more experienced Clan member to be able to provide helpful tips and things of the sort for our recruits. I've suggested an IRC but that might be too complicated for some people and having to go outside of CoC is not ideal. I think what would be really cool is to be able to create a chat room within CoC to communicate with people outside of your clan. I'm unsure of how much extra stress this would put on supercell servers but it would be easy to add into the current ui and would be welcome by many players.

Suggestions and feedback are welcome of course! If you currently have a system to talk across clans please let me know!