Oops, sorry. I did not see the part about the African cichlids. Keep in mind that African Cichlids require much harder water than most fish. You will most likely need to add some buffer to your water when you fill it up and every water change after that.
Are you planning on going with Mbuna's, or some other type. They are very nice fish. I have a small tank of them myself. They have great personality when they are over populated.
I was always under the impression that plants like softer water, so be sure to look into that before setting your plans in motion. I know there are a few plants that do well in hard water, but you can't get just any plant. Someone correct me if I am wrong on that.
Most of the African cichlid tanks I have seen do not have plants both because of the digging problem and the water hardness.