I've always used dithers in my grow out tanks which seems to calm them down. For juvi fish under 4-5" giant danios are what I use and later on they also what nutritious meals for your Cichla. Above 4-5" would all be up to you but you can use tinfoil barbs, bala sharks, large clown loachs, or any large shoaling fish that is too big to be eaten. Once your fish get to about 7-8" you no longer need dithers but I would recommend more than just two Cichla to create some competition between them which is going to be more fun for you feeding them and will also help them to get on a variety of foods.