Help!! Africans are Killing!!!

Question
Hi there. I am a newby, having only been keeping fish a few years, and cichlids for about 6-7 months. My Q is... I have raised a dempsey, 1 jeweled, 2 Kenyi(just turned colors, 1M 1F) 1 M Golden cichlid(turning black, guessing Male), 1 Blue Johanni, 1 unknown(inherited) no egg spots on the unknown, kinda bland brown so I'm guessing female. Along with these, I raised a jelly bean( was labeled a convict juvinile when purchased), and a severum which was considerably larger than the africans with no problems 'till now. I recently did a 30% water change and rearranged the tank to help with territorial disputes. Until recent, my jeweled was one of the tough guys, and the severum was too big to be messed with. Well, the Africans are about 3-4" and now my Jeweled wont leave the corner in fear. The severum just in a matter of a few hours today had 1/2 his top fin and a few scales removed. I'm not sure who's the bandidt, but I believe it was a pack mentality thing. NEVER, have the Africans even though abou messing with the peaceful severum.(hes about 5") I have moved the dwarf jellybean in with 7   1 1/2"-2" baby peacocks and she's doing better. I have the severum in thier tank with a divider. Some of the smaller are probably small enough to fit in the severums mouth. _Will he make a meal from my tiny colony??? _What can I do to stop the madness in my African tank??? I had such a beautiful tank for 6 months, but It's all going to Hell. Any ideas about stopping violence? Thanks in advance. P.S. I  know about keep Americans and Africans, but I've seen it done, I did until now:(

Answer
Hello,
I would like to point out that you never, ever mix South American Cichlids with African Cichlids.  The Severum is no match for the aggressive African Cichilds.  Always, follow the rules...Severums live in acidic, to neutral waters, and African Cichlids live in alkaline waters....nothing you can do to change this.  This is their character, this is their water, and this is the way they live.......forget about the guy who told you, you can mix them, you cannot, and this is now a problem.  The only way to solve this problem is to make a choice...either you want an African Tank of Cichlids, or a South American Tank of Cichlids...you cannot mix the two...it's like giving fish a headache to live with for the rest of their life.
Big fish will eat little fish... and some fish shouldn't have their babies removed from them as they look after them, and care for them.
To stop the madness, make sure you have lots of hiding places in rocky formation, and make sure that all your fish are either african of south american...you cannot mix the two!
Lynda