A toilet comprising a tank having a bottom, a bowl, and an attachment assembly configured to secure the bottom of the tank to the bowl. The attachment assembly includes a mounting bracket having at least three mounting locations spaced apart around an opening, a valve configured to fluidly connect the tank and the bowl, the valve being configured to engage the bottom of the tank and the opening in the mounting bracket, a valve nut configured to couple to the valve to secure the mounting bracket between the valve nut and the tank, and at least three fasteners configured to secure the mounting bracket to the bowl. The at least three fasteners are disposed external to the tank and couple the tank to the bowl without directly engaging the tank.