Cichlid compatibility

Question
My brother and I recently set up a 55 gallon aquarium. Right now we have a 5 inch plecostamus in it as well as some recently aquired african cichlids. We have two yellow labidochromis, two yellow auratus, an albino zebra, and three other unknown cichlid species that are all blue in color. I suspect one to be a kenyi, but of course I'm not sure and do not know what the other two may be. We also have a 2 inch rainbow shark and large emerald green cory in the tank. All of the cichlids are very small, approximately an inch long, and we bought them all around the same time to try and minimize aggression. We have had fish tanks in our lives since we were very little and both have had experience with our own tropical semi-aggresive tanks and decided to take it up a notch and go with cichlids. I am concerned however that since the cichlids can be aggressive, that they will attack the shark, pleco, and cory. At this point we had all three of them in the tank before the cichlids and they are bigger than the biggest cichlid. Do you think they will be okay together? We are also looking to add some more variety to the tank. Do you have any suggestions?

Answer
Hi Megan,
 For now, things should be fine.  As the cichlids get larger, you may have problems. The pleco will probably be fine but the other two might suffer badly. Also, keep in mind that you are mixing some very different fishes.  The East African cichlids prefer hard alkaline water, while the shark, pleco and cory prefer neutral to more acidic, soft water.

-- Ron C.
  rcoleman@cichlidresearch.com
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