We tend to use both our fireplaces only when we are up. We get home from work, turn it (downstairs) on, when the place warms up and we're ready for bed, we turn it off. I don't think we'll ever try to sleep with this one on..besides, it's sort of self limiting...
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Wifey didn't want a large LP tank outside, so I use a larger version of the grill tank. I think it's about 50% larger than the typical tank for a grill.
Pain in the neck to keep swapping out, but MUCH easier than lugging the 100 lb tank around, so I dont' use those. I have them as backup in case we get snowbound.