I figured that they were still small. You have three cichlids that are known to grow large and aggressive, especially the Red Devil. The reason they are fine now is because they are small enough to have space and a bit too young for their aggression to show. A 125 isn't a really big tank considering the size and temperment of the fish that you have. At around 5" you will start to notice a change in their behavior. This is when the fights will happen. These cichlids can be kept together but IMO a 125 is too small to keep them together peacefully. If you remove the Midas and red Devil, take the time to research any other cichlids that you may consider as replacements. You have to consider their adult size and behavior. I wouldn't add anything else. You should just let these grow out and see which will work. Then go from there. You may have to lose a few fish until you get it right. And there are many Pike Cichlids. Some grow to only a few inches while others grow to a foot or more. Their behavior and requirements differ too. You have to research the species that you want before adding it to your tank. As it is now I wouldn't add anymore. A Midas, Red devil, Cuban, Delhezi, and Red Wolf are already too much for a long-term stock. If you want to add something to make up the empty space while your stock is small, try some Giant Danios or some barbs.