Control Operations In Normal Operating Mode; Special Functions - Dennerle Comfort-line Exclusive DeLuxe Notice D'emploi

5.7.3 Checking the set pH value
• Press "pH" key: The green LED next to the key will flash; the display shows the set pH value.
• After 3 sec. the actual value appears again on the display, the green LED switches to continuously lit
mode and the controller resumes normal operations.

5.8 Control operations in normal operating mode

Example 1: Current pH value in the aquarium = 7.5. You set pH 6.8.
26
The green "CO supply" indicator lamp lights up.
2
is supplied (according to the number of CO
the pressure reducer). CO
the pH-Controller switches off the solenoid valve.
Example 2: Current pH value in the aquarium = 6.5. You have set pH 6.8.
The green "CO supply" indicator lamp does not go on. No CO
2
the aquarium rises above 6.9* will the pH-Controller reactivate the supply of CO
*When switching values of +/– 0.1 are preset (factory setting); see also point 5.10.2
5.9 pH value, CO
5.9.1 Why it is possible to set the pH value with CO
Some of the CO
2
extent to which the pH value is lowered is determined to a substantial degree by the carbonate hardness.
The carbonate hardness acts as a buffer and thus counteracts lowering of the pH value.
A precisely defined correlation always applies between CO
Table 1). When two values are known, the third can be calculated.
5.9.2 Setting the right level of CO
For magnificent plant growth, DENNERLE recommends a CO
30 mg/l, whereby 20 to 25 mg/l is ideal.
• Measure the carbonate hardness of the aquarium water (tests available from specialist retailers).
• Read the pH value which corresponds to the desired CO
the pH-Controller.
Example: Carbonate hardness 4 °d, recommended pH 6.8.
Important note: Only set such pH values and CO
carbonate hardness. Should you wish to set a pH of 6.5 for certain species of fish, for example, the car-
bonate hardness should be lowered to 2-3 °d. The CO
a prolonged basis.
See also the relevant literature on this subject or ask your pet specialist!
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The connected CO solenoid valve is open and CO
26
2
bubbles per minute set beforehand on the needle valve of
2
is supplied until a pH value of 6.7* is attained in the aquarium, after which
2
is supplied. Only when the pH value in
2
content and CO supply level
2 2
2
content in water dissolves to form carbonic acid, thereby lowering the pH value. The
content, carbonate hardness and pH (see
2
supply and the right pH
2
level in the aquarium of between 15 and
2
content from Table 1. Enter this pH value on
2
content levels as are tolerable for fish according to the
2
content should not be higher than 40 mg/l on
2
2
.
2
27
-
28
Table 1: Correlation between pH value, CO content and carbonate hardness
5.9.3 Setting the required level of CO
The CO supply rate (CO bubbles/minute) required to achieve the desired pH depends on a variety of factors,
2 2
such as the types of plants in the aquarium, motion of the water, surface area/volume ratio, etc. The
appropriate CO supply level thus requires to be determined individually for the specific aquarium concerned.
2
Rule of thumb for the basic setting: Begin at approx. 10 bubbles per minute per 100 l of aquarium water,
i.e. 2 x 10 = 20 bubbles per minute for a 200 l aquarium.
+
• Open needle valve slowly, initially only very slightly, until the first bubbles issue from the opening of the bubble
counter.
• Set the desired number of bubbles on the needle valve:
- Turn in clockwise direction to increase the number of bubbles
- Turn in anti-clockwise direction to reduce the number of bubbles.
Please note: There is always a certain delay before the number of bubbles changes in response to adjust
ment of the needle valve. The number of bubbles should thus be set with due care.
• After 1 day, check with the pH-Controller whether the desired pH value is achieved at this rate and the device is able to
perform its control functions in the correct manner, i.e. whether the connected solenoid is switched off intermittently.
• If not, the number of bubbles should be increased to approx. 15 bubbles per minute per 100 l of aquarium water. Check
again after 1 day. If necessary, increase the number of bubbles further in small steps until the desired pH is attained.
Please note: The more vigorously the surface of the water is set in motion (e.g. by filters, additional aeration),
the more CO will be expelled from the aquarium again.
2
• Check the number of bubbles regularly in the first few days, correcting as necessary. After this initial period it
is generally sufficient to check the number of bubbles once a week.

5.10 Special functions

5.10.1 Automatic pH setting
The "Auto" function enables the ideal CO
refer to the table:
• Press "Auto" key: The green LED flashes, the most recently set value appears on the display
setting: 04). Enter the carbonate hardness measured in the aquarium with "+" and "–".
• When the keys remain unused for 3 sec., this value will be adopted. The pH-Controller calculates the
exact corresponding pH value automatically and sets the system accordingly. The LED lights up in conti-
nuous mode.
• To check the set pH value: Press "pH" key: The set value appears on the display for 3 sec.
Example: Entered carbonate hardness 5 °d.
The pH-Controller sets pH 6.9 automatically (= 20 mg/l CO
• To switch off the "Auto" function: Press "pH" key and then enter the new setting with "+" and "–" while
the green LED is flashing.
Setting range: Carbonate hardness 1 – 20 °d.
supply
2
27
content (approx. 20 mg/l) to be set directly, without having to
2
(factory
28
).
2
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