6. CO₂, carbonate hardness (KH) and pH value
The three parameters CO₂ content, carbonate hardness, and pH value are inseparably linked, as they are interdependent� How much CO₂ is needed
to maintain a particular pH value depends on the KH in the aquarium� The higher the KH, the more CO₂ is required� Once the KH and pH values are
known, the CO₂ content can be calculated� The following table saves you making the calculations and also shows the pH values which you can set as
a set point without any risk to your fish�
Never set pH set point values arbitrarily� Always determine the KH in your aquarium first, e�g� with
JBL
PRO
AQUATEST KH
�
KH 2
1
2
2
3
4
5
6
8
10
12
15
24
38
pH 7,8
pH 7,6
pH 7,4
pH 7,3
pH 7,2
pH 7,1
pH 7
pH 6,9
pH 6,8
pH 6,7
pH 6,6
pH 6,4
pH 6,2
KH 10
5
8
12
15
19
24
30
38
48
60
75
KH 4
2
3
5
6
8
10
12
15
19
24
30
48
76
KH 12
6
9
14
18
23
29
36
45
57
72
90
KH 6
3
5
7
9
11
14
18
23
29
36
45
72
KH 14
7
11
17
21
27
33
42
53
67
84
KH 18
9
14
21
27
34
43
54
68
86
KH 8
4
6
10
12
15
19
24
30
38
48
60
96
KH 16
9
12
19
24
30
38
48
60
76
96
KH 20
10
15
24
30
38
48
60
76
95
Tabelle · Table · Tableau
CO
2
Too little C0
2
C0
2
correct
Too much CO
2
auto pH curve (see chap. 6.1)
C0
2
(mg/l)
6.1
The correct amount of CO₂ and the correct pH value
JBL recommends a CO₂ content of between 15 and 30 mg/l in aquarium water� This range is marked with “CO₂ correct “ in the table above� 20 – 25
mg/l have proved to be ideal� This level is not harmful to fish and at the same time promotes luxuriant plant growth� The menu point Auto pH uses the
mean value, namely 22�5 mg/l CO₂, as the basis to calculate the appropriate pH set point�
In special cases, e�g� for aquascaping, CO₂ levels of up to 35 mg/l may be necessary�
• Always start by measuring the KH of your aquarium water�
• In the section “CO₂ correct“ look for the pH value which matches the KH and the desired CO₂ value�
• Set this pH value as the set point on the device (see chap� 5)�
Please ensure that you only set pH values which are not harmful to fish� For example if the KH is high, do not set a pH value under 7�00� If you want
to set pH values below 7�00, a corresponding reduction of the KH is usually necessary�
Tip: If you activate menu point Auto pH (see chap� 7�5), the device automatically takes over the setting of an optimum pH set point which is appro-
priate for the KH of your aquarium and ensures luxuriant plant growth without endangering the fish� The corresponding values are given as the auto
pH curve in the table above�
6.2
Setting the CO₂ quantity
The amount of CO₂ which has to be added for the desired pH value depends on various factors, such as water movement, consumption by plants etc�
and has to be calculated individually for each particular aquarium�
• Begin with about 10 bubbles per minute in the
JBL
PRO
FLORA CO₂ TAIFUN COUNT SAFE
bubble counter per 100 l aquarium water�
• After one day check whether the set point entered has been attained in the aquarium and the device switches off the CO₂ supply now and then�
• Should this not be the case, increase the CO₂ supply to about 20 – 25 bubbles� If necessary, increase the supply in further small stages until the
device adjusts so that the CO₂ supply is switched off about 3 – 6 times per day�
Please also follow the instructions for use of the CO₂ fertiliser system you use!
7. The individual menu items
Description of attainability using the value overview (chap� 4)�
7.1
Language selection
Open with the following steps:
Settings key > select language > press OK > select the required language > press OK. To exit touch icon for “Settings”.
You can choose between 9 languages for the menu navigation shown in the display:
DE/EN-UK/FR/NL/IT/DK/ES/PT/RO�
7.2
Calibration
Open with the following steps:
Settings key > select Calibration > press OK > Start calibration > press OK.
The device now takes you step by step through a so-called two-point calibration� The device is first calibrated with 7�00 buffer solution and then with
4�00 buffer solution (never the other way round!)� See chap� 3�3 for carrying out the calibration and chap� 8�1 for further details�
Once calibration is complete, the time until the next calibration reminder is reset on the value overview (chap� 4) to 30 days/720 hours� This corre-
sponds to the factory setting�
The device needs to be calibrated because the pH sensor ages� The software used during the calibration process compensates this ageing, or gradu-
al change in the measured values�
7.3
Calibration reminder
Open with the following steps
Settings key > select Calibration Reminder > press OK > select the time interval > press OK.
This menu item offers you a choice of different times until the next calibration reminder� The following calibration intervals are available:
30 days
45 days
60 days
However we highly recommend you do not select the 60 days setting, since each pH sensor wears continuously and the measured values become
subject to change� The more often you carry out a calibration the more reliable the measurement results will be�
7.4
pH set point
Open with the following steps:
Settings key > select pH Set Point > press OK > select desired pH value using “plus” and “minus” > press OK.
The selected pH set point appears on the value overview (chap� 4)�
Please ensure you only enter pH set points which are indicated as “CO₂ correct” in the table in chap� 6�
As a further safety measure the carbonate hardness is calculated at the same time as the set point value� This means the set point is safe for the fish
and still provides enough CO₂ for the plants� In case the device calculates a KH value with more than 1° under the KH of your aquarium, make sure
that you want this value before confirming it with OK�
7.5
Auto pH
Open with the following steps:
Settings key > select Auto pH > press OK > enter desired KH value using “plus” and “minus” > press OK.
Enter the KH measured in your aquarium and the device automatically calculates the corresponding optimal pH set point which guarantees a CO₂
content of approx� 22�5 mg/l� This pH value is automatically stored as the pH set point when you press OK after entering the KH� This ensures luxuri-
ant plant growth without any danger to the fish� The values on which the auto pH function is based can be seen as auto pH curve in the table in chap�
6�
Auto pH is factory-set at 8 °dKH (German degrees)�
Tip: If you are unsure of the correct pH set point, always use the auto pH function�
Note: If the pH set point is changed to values outside the auto pH curve and the valve is set to „man“, Auto pH is automatically deactivated�
7.6 Hysteresis
Open with the following steps:
Settings key > select Hysteresis > press OK > enter desired value using “plus” and “minus” > press OK.
Hysteresis shows the switching points� In order to avoid the unnecessarily frequent switching on and off of the solenoid valve, an upper and lower
limit is set by which the measured pH value may deviate from the pH set point before the solenoid valve switches on� This protects the solenoid
valve from wear and tear� You can find an example for the control behaviour in chap� 5�1� Values from 0�1 up to 0�5 pH units can be selected� Factory
setting: 0�1 pH�
UK
UK
20
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