Heating a small cabin with hydroponic heat

[Fluenta]

Thanks all for the good advice and ideas (and spelling correction - oops). Reassuring especially to hear from folks in colder locations to give us confidence we can come up with a workable solution ourselves.

[Hunky Dory]

I had a gas engined i/o cruiser . I needed heat in the early spring and fall. I found a gas fired auxiliary Volkswagen van forced air heater. This unit was connected to a simple self contained thermostat and worked the same as a house furnace.( Do not use mercury thermostats, they don't like rocking of the boat The unit had its own fuel pump, spark plug ignition and forced air fan all in one small package. This unit worked great.

[Fluenta]

Quick update. Turns out the two hydronic boiler units I was given were beyond economic repair so we are going buy a larger used Eberspacher M12 (12 kW or 41,000 BTU/Hr). Rather more expensive, as with most boat projects, but this should let us reliably heat the aft cabin as well.