Why going thru all that hassle to store water ?
Is it a question of price ? Or a problem of container size (and then a problem of storage space) ? <img src="/images/graemlins/confused.gif" alt="" />

In any supermarket, I can find 8 liter (a bit over 2 US gallons) bottles of mineral water, with a max usage date 2 years from now. I guess it's much easier and safer too to store of few of these in my cellar (eventually protected from light by an opaque garbage bag).
A 2 gallons container is easier to move around. And when opened (and then susceptible to contamination), it will be used faster than a bigger capacity container : less risk to spoil.

Buying such a "bottle" every month is not expensive and then, once the stock is at the desired capacity, it's easy to rotate, using the oldest and replacing it.

I would eventually store treated tap water in previously used containers, not for cooking/drinking, but for other usage where the potability is not such a strict requirement (washing, flushing, a.s.o....).
Tap water being already treated, is it necessary to add more bleach to keep it for a long period ?