John,

        I know that you can by a water treatment that will inhibit the
growth of bacteria and algae in dehumidifiers.  It is usually
available wherever you can purchase dehumidifiers.  However, I don't
know anything about what sort of off-gassing problems may be
associated with them or what the chemicals may do to your outdoor
plants.



Patricia McElyea
Curator of Collections
Arkansas State University Museum
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