First: forget the one-gal. containers that you buy water in at the grocery stores. The opaque ones are biodegradable, and will turn to mush in relatively short time. They are also not durable, prone to leakage, and difficult to handle. I also live in a desert environment where the temperature soars to 115 degrees during the summer. I store a minimum of 100 gal. of water in two types of water containers:
As to treating the water:
Since I live in a metropolitan area, my whole preparedness program is geared to the phased Bug-out! For this reason, I store in no container larger than 5 gallons. The heavy plastic containers "plant" well also in the event that events "ramp-up", and it becomes necessary to establish water caches at intervals between your home and your destination...
Remember to plan on at least 4 quarts of water per day minimum for each member of your family in a hot dry desert environment. If you have the space, I would consider storing a good portion of the water in larger (30 to 55 gallon containers) to a three month supply. Also remember to re-oxygenate the water that has been stored by pouring it back and forth from one container to another....It improves the taste greatly!
Good Planning ~ Luck is not a factor!