D-tub Water Sanitation

The goal is to make a system that is not just technically safe, but compliant with public bathing regulations.  This is stricter than what's needed for a private tub, but if I'm picking up members of the public, I want to make sure it's safe for everyone (especially me, as I'll likely be in the tub more than anyone else!)

The on-board shower is a key feature for water sanitation, and it should have a big sign: "wash your ass".  Getting people clean before they get into the tub is probably more important than what happens after people get in.

• chlorinated with a chlorine injection pump
• large diatomaceous earth filter, which can filter out very small particles (like playa dust)
• copper and silver ions will also be added to water.  Though not officially recognized, this speeds up the action of the chlorine.
• regular PH and chlorine tests
• foot wash/skimmer for any floating bits, which goes right into the filter