Embodiments include a retrofit pontoon system including a pontoon, the pontoon having a pontoon body defining a first cavity, the pontoon body having a first aperture; a retrofit assembly, the retrofit assembly including a selectively fillable container sized to pass through the first aperture; and a pump. The pump is operably coupled with the selectively fillable container such that operation of the pump selectively fills and drains water from the selectively fillable container, wherein filling the selectively fillable container lowers the profile of the pontoon in the water and emptying the selectively fillable container raises the profile of the pontoon in the water.