Question About Manifold Connecting Propane Tanks

Interesting, you have two indicators where most of us have only one. My educated guess is that you have an automatic regulator. But instead of giving you a switch they just gave you two indicators. When one goes red you take that tank off and get it filled.

Assuming I'm correct I would say to make sure you always turn the same tank on first until it goes red. Then when that indicator goes red get the tank refilled and always turn the other tank on first until it's indicator goes red.