Page 69 - fish_farms_curriculum

Figure 28. pH measuring equipment (from left to right: pH meter with probe, electronic pH
meter, solution kit)

Oxygen Meter

Oxygen meters used to measure the amount of dissolved oxygen in water, which is a very

important parameter for both fish and bacteria, are of two types: membrane filter probe and
optical probe. The filters of membrane-filtered oxygen meters should be filled with KCl

solution and their electrodes should be cleaned over time. Calibration should be performed as
it is used. Oxygen meters with optical probes are calibrated with air and do not need to be

cleaned. It is easier to use and maintain. Oxygen meters measure temperature (C or F) and

oxygen saturation (%) besides the dissolved oxygen (mg/L) in water.

Picture 29. Oxygen meter (membrane filter on the left, probe with an optical filter on the
right)

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