ACJr. and Miwaukee PH PROBE DIFFERENCEs?!?!?

[ecvernon]

yesterday night i calibrated both probes for my milwaukee 122 ph controller and my ACJr.

the MLK 122 i used the 7.0 fluid and 4.0 and made adjustments
and made adjustments with the ACJr using 7.0 and 10 liquid. I followed manufacturer instructions for calibration procedures.


but the readings are always different

temp is 81.5
effluent /tank
MLK122 6.6/ 8.4
ACJr 6.50/8.11

API hirange na /8.2
liquid (don't have the salifert test kit yet i ordered it arrives (9/9/08)
I am not sure which one i would trust. the way i had it set up was ..
1.MLK controls effluent to stay at 6.5
2.ACJr controls tank ph. if it falls below 8.0 it is second defense to shut off power to the solenoid.

If any one has suggestions or similar problems input would be appreciated

 

[pecan2phat]

You can put 2 brand new probes in and they will almost always read different.

 

[meschaefer]

you also calibrated them differently

 

[NYreefNoob]

And You Should Have Used 7, And The 10.

 

[meschaefer]

And You Should Have Used 7, And The 10.

If he is using the probe to measure the effluent from his calcium reactor, using the 4 and 7 ph solutions is not necessarily a bad idea as the ph in a reactor is kept around 6.5 or so.

 

[ecvernon]

well that is why they recommended those solutions i guess. the mlk controller is often used for low ph. But at first before i bought the MLK i was using the ACJr to control the solenoid. Now I am really wondering if there is a 1.0 -1.7 varience in PH readings, what kind of affect will it have on the reactor.

I am guessing the ACJ was off because when i tested the effluent with the ACJ running the solenoid sometime last week it was running more concentrated(DKH30 AND CALCIUM560). now with the milwalkie dkh is 25