A Fairland family had a JoJo tank installed years ago. Five thousand litres of stored water sitting in the garden, topped up by rainwater and municipal supply. On paper, they were prepared for anything. In practice, every time Rand Water cut supply to the area, they were hauling buckets from the tank to the kitchen and bathroom.
The problem was simple: the tank was never properly connected to the house plumbing. There was no automatic switchover, no booster pump, no pressure equalisation. The tank was just a large container with a tap at the bottom. Useful for the garden, useless for the house.
We cut the main line after the meter and ran it into the tank through a float valve, then brought the booster pump back into the house main, so the house runs through the tank and pump every day. There is nothing to switch when the supply drops: the float simply stops filling and the tank draws down. A non-return valve after the meter means nothing can travel back toward the street. A pressure vessel keeps the pressure steady throughout the house.
The family did not even notice the last three water outages. They only knew because the neighbours mentioned it. That is the difference between having a tank and having a backup system.