The water will settle to the bottom of the tank. The fuel pump is located on the bottom of the tank which means it will be picked up first and sent to the injectors. Water will not burn so the car will not start or will but run rough and die. You can by a gas drier or pay less and go to the drugstore and buy some alcohol.
The only way to know for sure if a person has water in the gas tank is to drain the tank. Usually a car will sputter and die if there is water in the tank.
remove the fuel tank and drain the water
What will happen if water gets inside gas tank
skipping stall no start
bubbles on top of gas in tank
Water is heavier than gasoline, it will pool at the lowest point of the fuel tank.
Remove the tank from the car.
Yes, water is heavier than gas.
Have you tried using gas line antifreeze? That will help to remove some of the water in the gas. The best way to make certain all the water is out of the tank is to siphon the gas out, let the tank air out and re-fill the tank with gas from a station you know does not have water in the gas.
The hot water tank might be undersized for your usage.
Bad fuel fill.