PH controller

[ccs]

Been to the dennerle website and read the ph controller manual got this question.How is the controller connected to the co2 system perhaps someone kind provide a schematic of the connection?i.e from co2 cylinder to controller .

[vinz]

The general pH controller setup is like this.

You will need a solenoid on your CO2 cylinder. The solenoid is connected to the pH controller. The pH controller senses the pH of the tank water. When the pH gets too high, it turns on the solenoid, allowing CO2 to flow. When the pH drops too low, it turns off the solenoid and thus the CO2 supply.

Dennerle calls their solenoid, or equivalent, a "night cut-off valve".

[ccs]

Vinz,
Does that means that we would have to turn on the solenoid valve at the cylinder 24/7 but co2 flow is regulated by the controller?

[cherietung]

The solenoid valve is controlled by current. The PH controller is power on 24/7/52/365.

This measures the desired ph level and will switch on/off the solenoid to adjust the ph level.

Although Dennerle calls their solenoid "night cut off valve", it is not the case when you use a PH controller. If the ph level goes above your desired setting at night, the ph controller will switch on the solenoid valve to pump CO2.

Hope this answer your question and do get a PH Controller as it is good for planted tank.

[ccs]

Actually what i meant is the solenoid valve at the cylinder is usually controlled by a timer which will turn on the valve for certain lenght of the time.But if the flow as mentioned can be controlled by the ph controller then wouldn't it be better to use a manual valve at the cylinder side instead?

[tawauboy]

from your queries, i believe you understand a timer controlled co2 system setup. a co2 system controlled by ph controller has a similar setup to a timer controlled one, except the timer is being replaced by the ph controller. and co2 flow is not governed based on time but co2 concentration in your tank.

so the setup will have,
1) co2 cylinder – store co2
2) pressure regulator – reduce cylinder pressure
3) solenoid valve – to switch on/off co2 flow, controlled by ph controller
4) needle valve – to control flow rate