# help with my new pH controller.



## rick dale (Feb 26, 2014)

How do I know what to set it on? And what is the above and below switch for ? If it comes on or off at a set point , when does it come back on or off?


----------



## coralbandit (Jul 29, 2012)

I also have a drop checker so I could tell the co2 saturation in my tank.
If you don't have a drop checker you should get one for safety.
This chart is also another good reference;
CO2/pH/KH table - Aquarium Plants
It is worth going slow and being careful in the beginning if you have fish in the tank.
I use a timer with my controller to turn it on a couple hours before my lights and shut off a couple hours after lights.No need to waste co2 at night.


----------



## Gizmo (Dec 6, 2010)

Having never owned/operated a pH controller, but knowing quite a bit about sensing switches, I can suggest this as far as opening and closing:

Energizes solenoid (turns on CO2) at setpoint on increasing pH.
De-Energizes solenoid (shuts off CO2) at setpoint on decreasing pH.

pH lowers as you add CO2. Therefore, when the pH is high, you want more CO2. When the pH is high, the controller applies power to the solenoid to add CO2. When the pH lowers below the setpoint, the controller turns off the CO2.

Am I making any sense at all?


----------



## coralbandit (Jul 29, 2012)

If you could link the controller you got we could be more certain of what the switch is for?
It is possible you have to choose whether the controller keeps pH above OR below your set point?If this is how it works then you want it set for below IMO to keep pH below a certain level.A pH controller that works like this sounds a little "diffacult".
Mine gets set for" Target"pH and opens(turns on) the soleniod until the (lower) pH is reached.
The different settings would be for if you were adding co2 to freshwater or using co2 in a calcium reactor for marine IMO.


----------



## rick dale (Feb 26, 2014)

I am adding co2 to freshwater


----------



## nh murph (Mar 21, 2014)

My Milwaukee controller is set at below 6.8, and that gives me 30PPM according to my drop checker. Way too many variables to go by the pH alone. You'll want to invest in a drop checker.


----------

