Package2
This package brings you all the essential features of package 1 
but uses a Propane heater to heat the water.
The heater is a highly efficient water heater designed specifically 
for hot tubs. Water is self-circulating using the "thermo-siphon" 
principle. Hot water rises and creates low pressure, which sucks
 the water from below. 
This eliminates the need for a circulation pump and electricity, 
making it possible to heat the water with the heater placed 
externally.
The Propane heater is virtually maintenance free and weather 
resistant and not designed for indoor use.