LaMotte TOTAL HARDNESS TEST KIT PHT-DR-LT - Manual (Page 2)

PROCEDURE
1.
Fill the test tube (0608) to 12.9 mL line with sample water.
2. Add five drops of *Hardness Reagent #5 (4483). Mix.
3. Add one Hardness Reagent #6 Tablet (4484). Cap and swirl until
tablet disintegrates. Solution will turn red.
4. Fill the Direct Reading Titrator (0382) with Hardness Reagent #7
(4487DR). Insert Titrator in the center hole of the test tube cap.
5. While gently swirling the titration tube, slowly press the plunger to
add Hardness Reagent #7 (4487DR) until the red color changes to
blue. Read the test result directly from the scale where the large ring
on the Titrator meets the Titrator barrel. Record as ppm Total
Hardness as CaCO
3
.
EXAMPLE: Plunger tip is 3 minor divisions below line 80.
Test result is 80 plus (3 divisions x 4) equals 92 ppm.
6. If the plunger tip reaches the bottom line on the Titrator scale
(200 ppm) before the color change occurs, refill the Titrator and
continue the titration. When recording the test result, be sure to
include the value of the original amount of reagent dispensed (200
ppm).
7. To convert ppm Hardness to grains per gallon (gpg), multiply by
0.058. Record as gpg Hardness as CaCO
3
.
gpg CaCO
3
= ppm CaCO
3
x 0.058
ANALYSIS OF HARDNESS IN SALT WATER
When sea and estuarine waters containing very high levels of mineral salts
are tested, the sample must be diluted before titration. This test kit
contains a calibrated pipet for performing the dilution described below.
1.
Use the 0.5 mL pipet (0353) to transfer 0.5 mL of the salt water
sample to the test tube (0608).
2. Dilute to the 12.9 mL line with distilled water (a 1 to 25.8 dilution).
3. Follow Steps 2 through 5 above. Multiply the Titrator reading by
25.8. Record as ppm Total Hardness as CaCO
3
.
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PO Box 329 • Chestertown • Maryland • 21620 • USA
800-344-3100 • 410-778-3100 (Outside U.S.A.) • Fax: 410-778-6394
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09.09