Depends on conditions. Search here, and on the web for Civil Defense water info and you'll get some numbers. "How much" is really "How much do you need". 1 gallon per person per day includes washing hands, etc. and that would be about right. Strictly water consumption is of course much less than that, but in a water conservation situation you will be rationing your activity depending on conditions. Usually associated with desert survival scenarios.
Again, search here and elsewhere for the purification amounts, I can't remember off the top of my head. It is something like 1/4 cup for my 55 gallon drum, if that helps. When you purify the tank, you normally should not have a bleach smell. If you do then you have likely put too much, akin to amounts found swimming pool water