[URL="http/www.cichlid-forum.com/phpBB/viewtopic.php?t=135089"]http/www.cichlid-forum.com/phpBB/viewtopic.php?t=135089[/URL]
Is a good thread, made by a very knowlegable person (don't know if he has an account on this forum but he knows what he's doing). Though that topic is alot about breeding them.
How many cons are you giving to your friends parents? Might be wise to warn them about what could happen if a pair forms (lots of aggression and lots of babies - they might like to see the breeding behaviour but if they get attatched to the babies and cant give them away - almost impossible to do in most places - then maybe you should give them only females).
You could probably write a little booklet yourself about them, cons are easy fish to keep. Just inform them about water changes, correct diet, filtration and diet and it should all go fine really.