plete when specific conductance values at all sampling locations were
essentially the same.
The dye method indicates how long it takes to spread the dye over the
pond surface, but it gives no indication of mixing below the surface.
Moreover, the dye persists for several months (Boyd & Noor, 1982), and
the pond must be drained and refilled if a second test is to be done. The
salt-mixing test reveals the time necessary to mix the entire pond volume.
The salt solution which is poured into the pond is much denser than
water and does not mix well with surrounding water. Hence, this method
is only applicable to studying mixing by aerators which produce strong
water currents. The salt also raises the salinity in the pond, and only a
few tests can be conducted in a pond before it is necessary to drain and
refill the pond. The salt-mixing method is limited to fresh water.