Presently have a portable gas grill with 20-lb tank. Want to connect it to the 100-lb propane tank that also provides fuel for the fireplace. When they placed tank, a fitting was placed on the tank so that the grill could be connected. Have seen hoses for connecting natural gas - can the same hose be used? Is there a way to have a cutoff so that the gas is not always on to the grill?

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