Also how hard is it to breed Red Devils.
Adults are a pain in the

to get to pair off,I always thought red devils were hard to breed because I kept trying to pair of adults for years with almost no luck at all
seems alot of people have good luck breeding larger reddevils through deviders though - so thats an option
Young ones pair off easily almost to easy. If I pull babies my red devil pairs will spawn 2-3 times per month now - no extra work,just keep the tanks clean and at 82 degrees,most stuff I read suggested slightly lower temps but at 82 my fish are doing better and match the temp in my fishroom a little better.
As far as venting when you look at the fish - where they're reprductive organs are:
males will look like like one small and one large hole and females will look more like two even sized holes
I never explain it well,it's so much easier to show someone in person
check out
http://www.fishhead.com/articles/ventsex.htm for a decient explaination and some pictures of venting. That site suggests jeweler loupe's and stuff but for most new world species it can easily be done by just looking.