Hey Brian,
by the way, usually it’s not the CNC controller that switches the spindle coolant pump on and off, but the VFD. It’s the VFD that knows whether the spindle runs or not, because it’s the VFD that runs the spindle. That is why VFDs have relay outputs for spindle coolant pumps. See your VFD manual. Most VFDs also allow to let the spindle coolant pump to run a little longer after the spindle was stopped.