What is the stack temperature of the stove? The traditional way of accomplishing this is to run a stainless steel coil inside of the stove to circulate the water through, although with wood you would have problems with creosote build up. You would also need an expansion tank, a circulator, and two thermostats, one to turn the system on at a specific temperature, one to shut it down. It might be more cost efficient, easier, and more sensible to just simply run another duct off of your forced air system to your fishroom, and supplement that heat with some oil or propane wall heaters or space heaters.
Maybe best cost effective to separete basement heating/cooling from house?