So i just built my own indoor hot tub,and am now looking for a good external way to heat it.Cheap Suggestions?

Question

So i just built my own indoor hot tub,and am now looking for a good external way to heat it.Cheap Suggestions?

Answer 1

I put the pump, filter and natural gas heater outside the wall to the hot tub.  The controls are inside.

Answer 2

The solar panel I built last week would work during most of the year unledd you are too far north.  I used a double paned glass window (from trash)... made a wooden box from scrap... a sheet of tin siding and copper tubing...paint interior black with heat paint... boils water in 20 min.   Cost me about $50 for the copper, torch, solder and paint.  Allow water to circulate by convection when spa is off.  It will get HOT.

Answer 3

Buy yourself about 500 feet of black garden hose. Lay it in zig zag fashion out in the hot sun. When you feel the water is hot, turn on the spicket and fill the tub.