YSI 9300 Photometer - Manual (Page 95)

Test Instructions
1 Fill test tube with sample to the 10 ml mark
2 Add one Silica No 1 tablet, crush and mix to dissolve. Stand for five minutes to
allow the silica to react.
3 Add one Silica PR tablet, crush and mix to dissolve. (This stage may be
omitted if the sample is known to be completely free of phosphate).
4 Add one Silica No 2 tablet, crush and mix to dissolve. Stand for one minute
to allow full color development.
5 Select Phot 31 on photometer.
6 Take photometer reading in usual manner (see photometer instructions).
7 The result is displayed as mg/l SiO
2
.
Note
For testing high levels of Silica the YSI Silica HR test should be used. The range
of this test is 0 - 100 mg/l (see Test Instruction Phot 56).
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