Prototype 2:

After constructing and testing Prototype 1 a new redesigned pump was sketched. The new design's aim was to reduce the limitations and inefficiencies of the first prototype.

This was done through the following Features:

1.  Reduce diameter of rotors to reduce the torque required by motor.
2. Reduce overall height of casing to reduce material required and printing time.
3.  Reduce thickness of rotors to reduce weight.
4. Increase motor cut tolerance to ease assembly.
5. Reduce raceway diameter to fit smaller tubing.

Below are some CAD sketches for the new design: