I recommend a sump on all tanks if possible. @ a 29gal tank with a 10gal sump give a place for equipment,makes more room in the tank. Away to put more current in the water without powerhead = returns..seaswirls ect. A place for top off water changes ,additives,you can even make a refugium for pods,alga. It adds more water volume with is always good. When you have evaporation the tank says full ect ect ect......better skimmers are made for the sump. You don't need a big ugly hang on and if it floods less problem if its in the sump