Abstract: Disclosed is a system and method to convert a single flush toilet system to a multi-flush system. The system comprises of a flush selector that allows user selection of at least two flush modes, a flush water volume adjuster for each flush mode that allows the user to adjust the volume of water that flows from the water tank to flush the toilet bowl for each flush mode, a lifter that lifts the flapper of the toilet and allows water to flow from the water tank to flush the toilet bowl, and a hydraulic power source that powers the lifter to allow the adjusted volume of water to flow from the water tank to the toilet bowl and to flush the toilet bowl.