african cichlid tank

Question
I have just set up a Lake malawi cichlid tank for mbunas. I have placed rocks all the the bottom to form caves and made sure that they are secure. The substarate is crushed coral and sand from carribisea. The tank size is 30 gallons and is well filtered and oxygenated. I am from the southern U.S so I don't really need a heater during the winter. My question is can i keep 5 fish in this tank? I am planning on keeping an acei, electric yellow, for sure and i want to also get a bumblebee cichlid, red zebra, and a kenyi. Will they all work in this tank? Also is there any chance of cross breeding that you know of between these fish? Thank you for taking time to answer my question.

Answer
Hi Nick,
I would not keep the Bubblebee or the Kenyi.  The Bubblebee would get too big for your tank, is more aggressive than many other African cichlids, and they do kill.  I wouldn't recommend him.  The Kenyi should be kept in groups, and is not suited for a 30 gallon tank.  
They do cross breed.  I would stick to acei, electric yellows, red zebras.  Although aggressive, much less aggressive than the other fish you have mentioned.
Hope this helps.
Lynda