Handle...on a macerator???
Manual pumps have handles, but I don't know of any electric macerator that does. Based on your location, I suspect that you're looking at isn't maerator or pump at all, but the thru-hull on which the handle for the seacock has been removed...because on inland waters, it's illegal to dump a tank, and the authorities would require that the thru-hull be "permanently secured" in the closed position. Closing the seacock and removing the handle would satisfy that requirement.If your system is correctly installed for your waters, there should only be three hoses: a 1.5" ID hose from the toilet into a fitting at or on the top of the tank, a 1.5" ID hose coming from location at the bottom of the tank that goes directly to the deck pumpout fitting, and smaller vent hose coming off the tank at or on the top that goes to a thru-hull high on the hull. Any y-valves that allow the toilet to flush directly overboard or the tank to be dumped would be illegal in your waters. I think you'll find a lot of useful information in the articles in the head Mistress forum Reference Library (on the forum homepage). And I'll be glad to answer any questions they don't.