I am in the 1 for brewing, 1 for grill, and 1 for back up camp, all standard 20# tanks. I ran out 1 time even with these circumstances. The grill tank was not nearly as full as I expected it to be in the middle of winter: silly me, why would I expect it to be full in December? Luckily, I was just heating sparge water, ran for a refill and my mash was 120 minutes vs the expected 90. It all worked out and I am sure yours will as well