Over time they ended up building homes in this manner too and one of the brothers purchases the largest available plastic watertant on roof. Offended the other brother decided that he will build even bigger water tank. So they built a massive concrete water taken on the roof.
However the problem with this tank was that it would simply not retain the water which was pumped into it via a small motor pump which pulled the water from nearby well.
This resulted into the brother accusing the brother of "black magic" and engaging in daily fist fights and abuse.
Eventually someone figured out that the person who connected the intake pipe connected it at the bottom of the tank. So wehn the tank was full the water would simply go back to the well.