Here is a hint. There is a gauge on the tanks and when it gets to around fifteen percent call your supplier. It is not likely you own the tanks so the supplier will have you on a schedule anyway. Another tip do not let the tanks go empty. It will cause the supplier to think you have a leak and they will not fill the tanks until they send out a crew to make sure there is no leaks.

Hey jose',

It depends on too many things Jose.

The amount of hot water you use & how often you use it.

The inside temperature of your home & is it set at a constant , or only when someone is there?

How well is your home insulated?

The amount of hot water you use and how often you use it can turn on the water tank heater a lot

The hot water tank has a temperature sensor on it. So even when you use only 3 gallons of hot water, it turns the gas on to bring the temperature of the water back up again, because cold water filled it.

How often do you bath ? Once twice a day.?

Do you shower or take a bath? One uses more than the other.

If you shower you should get a shower head that makes a wider-finer spray.

They save water , so it will work for both hot & cold

Washing dishes: How often? Do you let them pile up a day or two, or wash each one after you use it?

Do you have a washing machine, & use hot water in it ?

Again,How often?

If you are heating a one bedroom apartment for 1 hour a day and using 1 gallon of hot water a day, they will last a long time.

If you are heating a 6 bedroom house for 24 hours a day, and constantly re-filling a 500 gallon hot tub, they won't last long.

Do you see the problem? If you want good answers, ask good questions.

if you are on automatic delivery they will fill it up regardless but it depends on how much YOU cook!

till they are empty

depends on how much propane you use.