I agree with Steve as far as having to tweak things along the way. My tank was constantly being tweaked in the first few years. Some fish just refuse to play nice, and they simply had to be swapped out with less hyper dominant specimens. As far as adult sizes, there is the norm, the below norm, and those that fall into the above norm. I have seen them all, including wild caught specimens. A friend from the past spent 6 months working for the late Stuart Grant on Lake Malawi, and one of the first things that he noticed when diving was how much smaller the Aulonocara all were, compared to the peacocks in his tanks at home. He assumed (correctly) that the fish in his tanks were getting fed more food, more often, than any of the wild fish, so over time they simply grew larger than norm.
On the flip side, some of the larger predatory haps far exceeded what one might see in an aquarium. Some were just very old specimens, that must have been living a good life, eating lots of smaller fish. I wish I still had the pic on my HD of a C. moorii that was collected while he was there. It was 11" TL. That fish along with most of the larger, higher $ fish went to a buyer in Japan.
I have seen plenty of larger domestic strains of C. moorii, but never one that was close to a foot long. Definitely an above norm specimen.