Dennerle Evolution DeLuxe Notice D'emploi page 29

14
29
7.3 Checking the set pH value
• Press "pH" button: The green LED next to the button 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 conti-
nuously lit mode and the controller resumes normal operations.
8 Control operations in normal operating mode
Example 1: Current pH value in the aquarium = 7.5. You set pH 6.8.
The green "CO supply" indicator lamp lights up.
2
and CO is supplied (according to the number of CO
2
needle valve of the pressure reducer). CO
aquarium, after which 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
value in the aquarium rises above 6.9 will the pH-Controller reactivate the supply of CO
9 pH value, CO
2
9.1 Why it is possible to set the pH value with CO
Some of the CO content in water dissolves to form carbonic acid, thereby lowering the pH value.
2
The 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
hardness and pH (see table). When two values are known, the third can be calculated.
9.2 Setting the right level of CO
For magnificent plant growth, Dennerle recommends a CO
15 and 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
Enter this pH value on the pH-Controller.
Example: Carbonate hardness 4 °d, recommended pH 6.8.
Important note: Only set such pH values and CO
ding to the carbonate hardness. Should you wish to set a pH of 6.5 for certain species of fish,
for example, the carbonate hardness should be lowered to 2-3 °d. The CO
be higher than 40 mg/l on a prolonged basis.
See also the relevant literature on this subject or ask your pet specialist!
The connected CO
bubbles per minute set beforehand on the
2
is supplied until a pH value of 6.7 is attained in the
2
content and CO supply level
2
supply and the right pH
2
content levels as are tolerable for fish accor-
2
solenoid valve is open
2
is supplied. Only when the pH
2
2
content, carbonate
2
level in the aquarium of between
2
content from the table.
2
content should not
2
.
2