I plan to install a storage tank for a gravity feed water system. The well/pump/tank is over 1/4 mi away from the house. No power nearby. So, I'm thinking of installing a big tank (10,000gal) that would hold enough water for a month. That way, I don't need any complicated control mechanism. I will just manually start the generator to pump water every once a while.

Any downside for having a big tank? Will the water go bad for being in the storage tank too long? How long will normal well water last in a tank when left untreated? I don't want to end up filtering and treating the water like a swimming pool. Thanks in advance for your comments.