Mixing Clowns is generally not a good idea. Some similar kinds (like Percs and Oscellaris) might get along, but Maroons are notoriously agressive and intolerant of any other Clowns. Including other Maroons! Mating them can be tough, so don't risk it. The Maroon will likely kill the other Clown.
I agree, might not be good idea. Never can tell, but to be safe...especially with a Maroon which is the largest and most territorial of the Clowns, I wouldnt try it.