JBL TestLab Handbuch Seite 37

Why test?
The following applies to freshwater and saltwater as well as to garden ponds (koi ponds):
The process involved in the breakdown or the mineralization of organic matter in the aquarium and pond (feed
and plant debris, fish excrement) follows the following stages: proteins - ammonium - nitrite - nitrate. Certain
bacteria are responsible for this process. Measuring the intermediate stages ammonium, nitrite and nitrate
allows certain conclusions to be made about the "function" of the system "aquarium" or the system "pond".
Normally, ammonium and nitrite should not be allowed to enrich concentrations of above 0.2 mg/l (ppm). If they
do, the bacterial balance may be disturbed. Many of the medications used to treat fish diseases can damage
beneficial cleansing bacteria, leading to an increase in ammonium levels. As a rule, ammonium is not found in
measurable amounts in a well-maintained aquarium with an efficient biological filter or in a correctly planted
garden pond. Ammonium is an important plant nutrient and is normally non-toxic to fish. But, depending on
the pH value, the ammonium ion (NH
ammonia measurement should always be accompanied by pH measurements. The following table shows the
toxicity as factor of the pH value (at 25°C):
May be harmful to sensitive fish and small fry.
May be harmful to adult fish, very harmful to young fry.
Very harmful to adult fish, lethal for small fry.
Absolutely lethal for all species of fish.
NH
4
mg/l
0,1
ppm
pH
7,0
7,5
8,0
8,2
8,4
8,6
8,8
9,0
Remedy:
Short-term measure (aquarium only) :
Change about 50 % of the water. Do not allow the pH level of the freshwater to exceed the pH level of the
aquarium.
Long-term measure:
Aquarium:
Add cleansing bacteria with JBL Denitrol and JBL FilterStart.
Use a suitable biological filter. Reduce feed, reduce density of fish stock, if necessary.
Garden pond:
Add cleansing bacteria with JBL BactoPond and JBL FilterStart Pond. If not already in use, install an efficient
pond filter. If necessary, review general design concept of pond: is there sufficient ground-covering material,
marshy area, working as a plant based purification system etc...?
) may convert into ammonia (NH
+
4
0,2 0,4
) which is toxic to fish. This is why any
3
0,8
1,2
35
2,0 3,0
UK
5,0