Help regarding use of propane regulator

Look at your propane regulator. That is the item near the top of the propane tanks that has two hoses that connect to the tanks. There is a gauge that will show green (still has propane in it) or red (empty). There is a device, either a knob or lever with an arrow or just a tab. That lever or knob/pointer will be pointing to the tank that is in use. If the gauge shows red, what you do, is turn off the valve at the top of the tank that the lever is pointing to and flip/turn that lever to point at the other tank with propane. When you do that, the gauge will turn to green indicating the presence of fuel. NOW it is safe to remove the empty tank and have it refilled. When you return, just put it back in place connect the hose firm but do not over tighten. Open the valve at the top of tank very slowly,  and it is ready to go.    At this point I like to take a bit of soapy water (bubbles) and with a sponge or brush dribble some over the connections to check for leaks. You don't need to touch that lever/knob until the gauge shows red again and then repeat as outlined. I hope this is clear.

How to Check the Level of Gas in you Propane tank

Pour very hot water slowly down one side of one tank from the top. Then slowly slide your hand down the side where you poured the water and you will feel a definite difference in temperature. Where the cold starts, is where the level of propane is.