Hi Mike,
If the fresh water has never been sanitized here is the condensed version. Pump the fresh water into the gray tank thru the kitchen or lavy sink if you are not allowed to dump onto your site. Turn off your AquaHot and pump all the hot water out until cold water comes out of the faucet. Carefully pour 6 to 8 ounces of bleach into your city water hose and reinstall at your supply spigot. Fill the fresh tank turning on the "fill switch" until the monitor panel states FULL. Turn on your pump and open each fixture until you smell chlorine bleach. Don't forget the washer/dryer, outside faucet, insta-hot, and ice maker. Do the same with the hot water side. Let the solution sit for 4 hours to disinfect the entire system. Pump the entire solution out of all fixtures and refill the tank 3 times to flush out residual bleach. Mix a small box of baking soda and water in a quart container. Fill your city water hose with the solution and connect to your supply spigot. Fill your fresh water tank until full. Open each fixture the same amount of time it took initially to detect the bleach odor. Let it sit for 2 hours and flush twice, Replace all your water filters and refill. The owners manual has the procedure if I forgot anything. I do this once a year for peace of mind not knowing about the water supply across the country. Hope this helps, Fred