Recommendation: Re-home the dimidiochromis compressiceps and cyrtocara moorii, then add more yellow labs.
D. comps get upwards of 10-11", and blue dolphins max out at 7-9". Both are open water haps (6ft tank minimum for the eye biter and 90gal-125gal minimum for the blue dolphin).
Better recommendation: get a larger tank (55gal minimum for yellow labs as is the case for most mbuna species; a smaller tank such as the 36gal may work for some yellow labs as they are usually on the lower end of the aggression scale. Multiple male yellow probably not do-able when thinking long-term (target group 1m/4f).
Small group size amplifies aggression. Small tank size does too, so a small group size in a small tank will almost always lead to aggression problems (when stocked with rift-lake african cichlids, excluding shellies).
Rift Lake and Reef tanks.