A liquid mixing infusor includes a main body defining an internal chamber and has an upstream port, a downstream port and a confluent port. Each port is fluidly couplable with the internal chamber. A valve may be mounted within the internal chamber of the main body and is adapted for rotational movement between a blocking position interrupting fluid flow between the confluent port and one of the upstream port and the downstream port and between the upstream port and the downstream port, and a flow position permitting fluid flow between the upstream port and the downstream port. A manually manipulative member is mounted relative to the main body and operatively connected to the valve. The manipulative member is movable to cause corresponding movement of the valve between the blocking position and the flow position.