YSI 9300 Photometer - Manual (Page 92)

Test Procedure
1 Fill test tube with sample to the 10 ml mark.
IN THE CASE OF SAMPLES CONTAINING SILICA (>20 mg/l SiO
2
) ONLY :-
2 Add one Phosphate SR tablet, crush and mix to dissolve.
3 Add one Phosphate HR tablet, crush and mix to dissolve.
4 Stand for 10 minutes to allow full color development.
5 Select Phot 29 on photometer.
6 Take photometer reading in usual manner (see photometer instructions).
7 The result is displayed as mg/l PO
4
.
NOTE
Phosphate SR tablets are supplied in the Phosphate HR Starter Pack (PM 114).
They are subsequently available as an optional extra (AT 116) for use with
Phosphate HR Replacement Reagent Packs.
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