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The pH Pal digital pH meter contains a special probe which
measures the pH of water. The end of the meter is dipped
into the pond and then switched on. After a short time, the
display will settle and pH of the liquid will be shown on the
LCD readout. The meter can be calibrated by an inset screw
at the back of the unit.
The meter is straightforward to use and is accurate making it
great value-for-money