PH Controller/Monitor & Grounding Probe

[ASpec]

I've read a couple people state when running a PH controller or PH monitor that you should have a grounding probe installed since stray voltage will cause the PH to read low.

I've looked around the forum and while I've found some good threads regarding grounding probes I have yet to find any specifc information regarding the use of one when using a PH controller or monitor.

I'm asking because I just setup my FW tank, today I added the SMS122 controller. My PH out of the tap is around 7.8, I set the controller to 7.0. My PH has since dropped to 6.5... so I'm starting to wonder if my PH controller is reading low due to "stray" voltage?

Any thoughts on this?

I don't have my GH/KH test kit yet (should be here Monday/Tuesday) so I could not tell you my CO2 level right now. My PH test kit does not read below 7 (It's a high range test kit, ordered a low range kit already).

Thanks!

 

[greenmaji]

Did you calibrate your controller?
What brand is it?
I personaly doubt its the "stray voltage problem"
I remember people encourging grounding probes in case of an electrical problem with submerged electrical equipment, like a powerhead or heater breaking.. not are alot of people using them now.

 

[Xzap]

As green asked, the first thing we need to know is did you calibrate the pH probe first ?
I hear of a lot of people using them right outta the box and you can't do that.

Dave

 

[ASpec]

Thanks for the response. Yes, I did calibrate the controller. It's a Milwaukee SMS122 controller. I'm using a Milwaukee MA957 CO2 regulator with the controller and a DIY reactor.

The tank is empty, no fish/no plants so I am not endangering anything... just curious why my PH is reading so low. I plan to add plants this week to begin the cycle.

Any other ideas?

 

[greenmaji]

what are you reading the PH with? the readout on the controller? a PH testkit?
is is the controller opening the silinoid valve when the PH is reading under 7.0?
if your PH is 6.5 and the controller isnt letting any more CO2 into the tank..
Maybe your KH reading will clear things up for us.. If your KH is under 3 you might be needing to do more water changes to keep the PH from droping qickly. or buffering the water with baking soda.

Im thinking it might be the KH or.. your tank got a good dose of CO2 and your controller is just waiting for the PH to come back up to dose more CO2 again, and its not happening without a water change or some aggitation of the water surfase.

there is a good chance that your controller will be closer to being able to giving a correct PH reading then a testkit.
just some thoughts...

 

[ASpec]

I'm also interested in seeing what my KH is.

The PH has dropped down to 6.0 today. I'm getting that PH level off the meter, since I only have a high range PH test kit at the moment. Hopefully my GH/KH and new PH test kits will arrive early this week.

I guess you could be correct in the fact the inital dose of CO2 when the controller had the silinoid open (the PH was above 7) has been able to stay within the water. Nothing to obsorbe that CO2, no turbulance on the water surface, no air stone, and a glass top.

Thanks for the advice!

 

[greenmaji]

Im asuming the controller is working and it hasn't kicked back on from your responce.
If you had plants in the tank they would be absorbing the CO2 bringing the PH back up..
I would wait and test the KH before moving forward though.

no problem

 

[Brenden]

I use a ph monitor and do not have a ground probe. I have checked it (ph)several times with kits and it matches the monitors results.