20
Nitrite (NO
2
)
Test procedure:
1. Take a water sample of 5 ml.
2. Add 5 drops of NO
2
test fl uid.
3. Shake well.
4. Wait 5 minutes.
5. Determine the NO
2
-value using the included colour chart.
Nitrite (chemically abbreviated as NO
2
) is produced out of ammonia
by the nitrifying bacteria in your aquarium or pond. As nitrite is highly
toxic to all water life, it is vital that the nitrite level in the water is zero.
The best way to harbour these bacteria is in a biological fi lter. A new
‘clean’ fi lter needs time to have a suffi cient number of bacteria to grow
inside it. You can give this growth a boost by adding the right type of
bacteria from the moment the biological fi lter is started. For all types of
water, Colombo has the right product with the right bacteria: Colombo
Bactuur for fresh water aquaria and for ponds.
An optimal nitrite level in all kinds of water is simply 0 mg/l. When the
nitrite level is 0.5 mg/l or higher, it means that aren’t enough bacteria
present and thus it is wise to add Colombo Bactuur. Add Colombo
Liquid Filter to your tank or Colombo BiClear to your pond to bind and
detoxify the ammonia; in this way also the production of nitrite from
ammonia is blocked. At a nitrite level of 1.0 mg/l, nitrite can become
toxic, and thus it is wise to fi rst refresh 25% of the water. At nitrite levels
20ml
15ml
10ml
5ml
5 min
5
20ml
15ml
10ml
5ml
4
3
5 dr
ops
20ml
15ml
10ml
5ml
2
5 ml.
20ml
15ml
10ml
5ml
1
NO
2
