10°C
pH
Fresh
water
1
7.0
0.19
7.1
0.23
7.2
0.29
7.3
0.37
7.4
0.47
7.5
0.59
7.6
0.74
7.7
0.92
7.8
1.16
7.9
1.46
8.0
1.83
8.1
2.29
8.2
2.86
8.3
3.58
8.4
4.46
8.5
5.55
Freshwater data from Trussel (1972).
1
Seawater values from Bower & Bidwell (1978). Salinity for Seawater values = 34% at an ionic strength
2
of 0.701 m.
FOR EXAMPLE:
A fresh water sample at 20°C has a pH of 8.5 and the test result is 1.0 ppm as Total
Ammonia.
1.
The percentage from the table is 11.18% (or 0.1118).
2.
1 ppm Total Ammonia x 0.1118 = 0.1118 ppm Unionized Ammonia
3.
Total Ammonia
Unionized Ammonia
Ionized Ammonia
To convert Ammonia (NH
To convert Nitrite (NO
To convert Nitrate (NO
15°C
Salt
Fresh
water
water
2
—
0.27
—
0.34
—
0.43
—
0.54
—
0.68
0.459
0.85
0.577
1.07
0.726
1.35
0.912
1.69
1.15
2.12
1.44
2.65
1.80
3.32
2.26
4.14
2.83
5.16
3.54
6.41
4.41
7.98
) to Ammonia-Nitrogen (NH
3
) to Nitrite-Nitrogen (NO
2
) to Nitrate-Nitrogen (NO
3
20°C
Salt
Fresh
water
water
—
0.40
—
0.50
—
0.63
—
0.79
—
0.99
0.665
1.24
0.836
1.56
1.05
1.96
1.32
2.45
1.66
3.06
2.07
3.83
2.60
4.77
3.25
5.94
4.06
7.36
5.05
9.09
6.28
11.18
1.0000 ppm
_
0.1118 ppm
=
0.8882 ppm
-N) multiply by 0.823
3
-N) multiply by 0.304
2
-N) multiply by 0.226
3
14
25°C
Salt
Fresh
water
water
—
0.55
—
0.70
—
0.88
—
1.10
—
1.38
0.963
1.73
1.21
2.17
1.52
2.72
1.90
3.39
2.39
4.24
2.98
5.28
3.73
6.55
4.65
8.11
5.78
10.00
7.17
12.27
8.87
14.97
Salt
water
—
—
—
—
—
1.39
1.75
2.19
2.74
3.43
4.28
5.32
6.61
8.18
10.10
12.40