permaculture

["John Schinnerer" <john@eco-living.net>]

Aloha,

Chlorine is the standard pool/tub critter-killer.  Pretty nasty - we take
in more through our skin than though drinking, BTW.

In conventional circles, bromine is a less-nasty alternative that would be
known to typical pool/tub suppliers.

Other options I'm aware of are ozonation, and UV (ultraviolet) treatment,
both for killing unwanted critters growing in pool/tub water.

If you've got enough sun and can put it below the level of the bottom of
the tub, you can hook a thermosiphon solar water heater setup (commercial
or DIY) to it for heating the water.

Beware of direct paths for the humidity the hot tub (and greenhouse) will
produce to enter your dwelling (unless you're in an arid climate, where it
might be more of a blessing).  Mold and mildew in your dwelling is usually
not good for your health...  :-p



John Schinnerer, MA
-------------------------
- Eco-Living -
Cultural & Ecological Designing
People - Place - Learning - Integration
john@eco-living.net
http://eco-living.net