I'm with Jimini
Keep it simple, the fewer pumps, long hoses,stepper motors the better.
I say use a fixed gantry with Y axis moving your three hot pots right above your moving X table with solenoid valves on the bottom of your pots and gravity feed, easy to heat up easy to clean few things to go wrong. Now you just need 2 axis and three on off signals.

onthemarc