Yah they are slow growers so if you get the fronts I suggest getting young ones but once they grow up you'll have to get them a bigger tank - so if you dont plan on getting at least a 125gal althought If you plan to stock up on fronts then I suggest a minimum 180gal. then I would stay away from the fronts. Tangs would def. make a cool tank here are fish I would consider (I wouldnt throw them all in a 55gal just pick what you like): both alto comps and calvus would be cool along with, Tropheus Duboisi, Ectodus descampsii (stay small though so maybe not), Neolamprologus brichardi, Xenotilapia, Cyathopharynx foai, Cyprichromis leptosoma, Chalinochromis sp. "ndobhoi", Neolamprologus helianthus, Neolamprologus leleupi, Neolamprologus olivaceous, Variabilochromis moorii.