YSI 6 series User Manual page 52

Sondes Section 2
water. Input the value 0 NTU at the prompt, and press Enter. The screen will display real-time readings
that will allow you to determine when the readings have stabilized. Activate the wiper 1-2 times by
pressing 3-Clean Optics as shown on the screen, to remove any bubbles. After stabilization is complete,
press Enter to "confirm" the first calibration and then, as instructed, press Enter to continue.
Dry the sonde carefully and then place the sonde in the second turbidity standard (100 or 126 NTU is
suggested) using the same container as for the 0 NTU standard. Input the correct turbidity value in NTU,
press Enter, and view the stabilization of the values on the screen in real-time. As above, activate the
wiper with the "3" key or manually rotate the sonde to remove bubbles. After the readings have stabilized,
press Enter to confirm the calibration and then press Enter to return to the Calibrate menu.
Thoroughly rinse and dry the calibration cups for future use. For additional information related to
calibrating the turbidity sensor, see Appendix E, Turbidity Measurements.
CHLOROPHYLL 1-POINT
Select Optic X -Chlorophyll from the Calibrate Menu, Chl µg/L and then 1-1 point.
NOTE: This procedure will zero your fluorescence sensor and use the default sensitivity for calculation of
chlorophyll concentration in µg/L, allowing quick and easy fluorescence measurements that are only semi-
quantitative with regard to chlorophyll. However, the readings will reflect changes in chlorophyll from site
to site, or over time at a single site.
To increase the accuracy of your chlorophyll measurements, follow the 2-point or 3-point calibration
protocols outlined in Section 2.9, Sonde Menu.
Before making any field readings, carefully read Section 5.14, Chlorophyll and Appendix I, Chlorophyll
Measurements that describe practical aspects of fluorescence measurements.
To begin the calibration, place the correct amount (see Tables 1-8 above) of clear deionized or distilled
water into the YSI clear calibration cup provided. Immerse the sonde in the water. Input the value 0 µg/L
at the prompt, and press Enter. The screen will display real-time readings that will allow you to determine
when the readings have stabilized. Activate the wiper 1-2 times by pressing 3-Clean Optics as shown on
the screen to remove any bubbles from the sensor. After stabilization is complete, press Enter to
"confirm" the calibration and then, as instructed, press Enter to return to the Calibrate menu.
Thoroughly rinse and dry the calibration cups for future use. For additional information related to
calibrating the chlorophyll sensor, see Section 5.14, Chlorophyll and Appendix I, Chlorophyll
Measurements.
BGA-PC 1-POINT
Select Optic X BGA-PC - from the Calibrate Menu, and then 1-1 point.
NOTE: This procedure will zero your fluorescence sensor and use the default sensitivity for calculation of
phycocyanin-containing BGA in cells/mL, allowing quick and easy fluorescence measurements that are
only semi-quantitative with regard to BGA-PC. However, the readings will reflect changes in BGA-PC
from site to site, or over time at a single site.
To increase the accuracy of your BGA-PC measurements, follow the 2-point calibration protocols outlined
in Section 2.9, Sonde Menu.
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