LaMotte Water & Soil pH User Manual

Page 7

TESTING WA TER
TAKING WA TER SAM PLES
Carefully follow the suggestions below for taking water samples.
1. The water sample should be representative of the source and free of

any foreign matter, such as aquatic plants and sediment from the

bottom.

2. The container should be clean and free from particles. Use a plastic or

glass container with a screw cap that is large enough to hold water for

all desired tests.

3. Unless the sample is to be tested immediately, the container should

be filled until it overflows, and then capped. This procedure

eliminates the possibility of getting air bubbles into the sample. A

container which is only half full with water is subject to chemical

changes caused by oxidation while being transported. Generally, the

best results are achieved by testing the water as soon as possible.

4. If the sample is taken from a tap, it is important to let the water run

for several minutes before taking the sample.

TESTING THE pH OF WA TER
1. Use a clean pipet (0354) to fill a test tube (0755) to line 2 with

sample water. (See Figure 3)

2. Add 10 drops of Tricel Indicator (5945). Cap and mix.

NOTE: Hold dropper bottle vertically. (See Figure 4)

3. Hold tube flat against white area of Wide Range Color Chart (1353).

Match sample color to a color standard. Record as pH. (See Figure 5)

Fig. 3

Transferring

portions of

Fig. 4

Adding drops

of Tricel

Indicator.

Fig. 5