I got one of those cheap green scale gauges from AMAZON something like this one for each of my two tanks. It seems like it always says it is the green until all of a sudden it goes to empty. Does not do a gradual change in reading as it is being used..
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I usually run my hand along the tank in the morning and I can feel the cool zone where the gas level is. Alot of times in the morning you can actually see the sweat line...
My real problem is I always turn off the tanks when in travel and I forget which one I am using. I'd like to use the same one until it goes empty. I guess I need to hang a D-link snap ring hook or something on the valve of the tank that is in use.. Then at my age I'd probably forget if the hook means it is empty or the one I am using - go figure...
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Roy Ken