I use a combination of 5, 15, 30 and 55 gallon containers most purchased through Emergency Essentials. I took a couple old pallets and cut them in half, and keep the barrels off the floor. I flush and refill them about every year (at the summer solstice), although I'm thinking of going to 18 or even 24 months with some of them, I haven't noted any appreciable taste or quality issues so far. Looking for leaks as well, none so far. I don't treat with bleach during storage, I do use a bleach solution when the container is empty and I want to rinse it out before refilling: if I use bleach, it would be to treat stored water. I also rotate a small container of bleach every time I refill the water, that stuff also expires and 1 year is about its limit.

My only bright idea on water is to mark the container with the fill date so you may know that its time to refill. Maybe another bright idea: I keep water in more than one place in my household, some in the garage, ~1 week supply in with our food supply, and more in a cool, dark back room, in the event the house collapses (earthquake is our #1 local disaster that might prompt us to drink stored water) I have a shot at digging out at least some of the water. The garage water (most vulnerable to collapse) is actually in a very sturdy metal rolling cage (bought from a surplus store) that should provide some support from a collapsing structure.