It can. The "trick" is to get the burn tunnel insulated enough to burn clean and not make it so huge to overwhelm the water tank.
The same kind of product USED to exist for cattle stock tanks that used wood. It was bigger and straight because it was made to fit in a 8 foot round tank. It looked like the J tube for a rocket stove without the barrel (the riser became the chimney) but was not insulated and didn't burn as clean.
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