I have 6 30 gallon and 6 6 gallon, plus 35 gallons in the Roadtrek (small motor home). So a total of 160 gallons of treated tap water, plus 2 cases of small bottled water and 12 gallons of bottled water in gallon containers. This is my "standard" reserve.

I also use a hose designed for water, not just the garden hose, and sometimes, the pre-filter like you would buy at an RV store to use when you're on shore power/water.

To treat the tap water, I use the stuff I buy at the RV store, the sodium dioxide mentioned above. I have had the RV water sit for >6 months and it's still palatable, the action of pulling it from the tank to the tap/shower probably aerates it some.

I got the 30 gallon (Baytec Containers, on line, free shipping) so they could be easily moved by dolly, or even rolled on edge. I use a plastic siphon (also baytec) to move the water from the 30 to the 6 gallon (as I empty them) so it can be easily carried into the house. Plus I believe it re-aerates the water as it is transfered.

Even though the sodium dioxide makers state the water can be stored for 5 years, I usually change it every 6 months or so. But I'm careful where it's poured since the sodium dioxide is a corrosive, though slight.