N˚

Parameters

1A

1B

2

3

1

Temperature (˚C)

≤20

20 - 22

22 - 25

25 - 30

2

pH

6.5 - 8.5

6.8 - 8.5

6 - 9

8.5 - 9.5

3

TSS (mg/l)

≤30

≤30

≤30

30 - 70

4

Nitrates (mg/l)

-

-

≤44

44 - 100

5

Phosphates (mg/l)

<0.1

0.1 - 0.3

0.3 - 0.5

0.5 - 3

6

COD (mg/l)

<20

20 - 25

25 - 40

40 - 80

7

BOD (mg/l) (5 days at 20˚C)

<3

3 - 5

5 - 10

10 - 25

8

EC

≤400

400 - 750

750 - 1500

1500 - 3000

9

DO (mg/l)

>7

5 - 7

3 - 5

<3

10

${\text{NH}}_4^{+}$ (mg/l)

≤0.1

0.1 - 0.5

0.5 - 2

2 - 8