If you own a gas grill then at one point or another you've undoubtedly encountered this common scenario: You've got all your food prepped, various fixings like ketchup and pickles ready to go, and it's time to start grilling... until you realize you've run out of propane. Yikes! It's bad enough when it happens to just you and your immediate family, but when you've got a big party full of hungry guests? It's a downright nightmare.
While some tanks actually come with a very handy gauge built into them, a lot of them (including all the ones I've ever encountered) do not. Checking the levels on these can seem like guesswork, but here's one very clever trick to find out. All you have to do is boil some water and slowly pour it down the sides of your tank. Then, use your hand to feel for heat. Propane will tend to absorb some of the heat from the boiled water, resulting in a cooler temperature on the tank's surface. Thus, the point at which your tank starts to feel cool to the touch is where the current gas level is. Genius, right?
Alternatively, you can also weigh an empty tank, then get a full tank of the same size/brand and weigh that. Now, you can simply weigh your tank anytime you're unsure and use your Full/Empty reference numbers to calculate how much of the tank you've used.