The tanks let you store water so your pump is not running as soon as you turn on water. Having two tanks will let your pump not turn on as often as it is now. When the pump turns on it will run longer. Having a pump short cycle is not a good thing. Kind of like starting a car then turning it off a second later.Originally Posted by Roundtown
When houses are built installers tends to use the bottom of the sizing chart when it comes to pumps and tanks. Adding the second tank may bring you closer to the size that you really need. Was the second floor added after the house was built.
I have seen 5 tanks in a house but it was a very large house.