Not sure what you about a water tank, but I have an amazing wood stove made out of a large outdoor propane tank cut in half. It has the stove pipe exhaust not at the top of the stove, but a little further down to increase heat circulation. Nice air tight door on front. It has some simple legs on it. It also has a flat top for cooking and heat distribution. Extremely efficient for a traditional wood stove.
You didn't tell me he was so big. Unlike this tiny ad:
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