While I handled some papers that could not wait, John got a hose running from our irrigation line. (No sewer tax on it, so fairly inexpensive.) The pics show about 1800 gallons per our meter. Sometime before dawn we'll know how many gallons it can take.
As for fully functional, well ... John says he will be done by Saturday morning with his multitude of remaining tasks, assuming rain, hail & tornados stay away.
While the focus has been on spraying, John has been proceeding with the plumbing and filtration. Each Nexus has its own Sequence pump, and a third is in place to serve the bead filter. (It will be moved into the pit at the end, since it is filtering the holding tank right now.) And, we have a water tap (operational) from the irrigation line into the pit.