AC3 pH probe question

hionreef

New member
I just got an AC3 with temp/Lab pH probe. I calibrated it but I am not sure if it is reading correctly. When I test aerated DI water I get ~ 7.0, but when I test a saltwater mix (reefcrystals at 1.026 using calibrated hydrometer @ 78F) I get ~ 8.2.

I have another handheld probe (calibrated, etc.) that Ive been using and when I test the same batch of saltwater I get a pH of 8.4 (which is about what I would expect).

Anyone else with these ever have a bad one right out of the package?

thanks
rich
 

jthao

Super Saiyan
that's weird.... once calibrated it should be pretty accurate. my ac3 with the regular probes work fine. go to the neptune systems forum, Ken is an expert on these things, he should be able to help you.
 

hionreef

New member
The AC was brand new - the other I have is several years old but still seems to output closer to what I would expect.

thanks - Ill check the forum...
 

Brian Prestwood

Premium Member
Hey Rich

You could have an electricity leak in the tank. Test the tank water in an electronically isolated environent, e.g. a glass, instead of the sump and see if you get different reading.
 

Doahh

New member
If it reads the calibration packets as 7 and 10 then that probe is right... test the handheld one in the calibration packets
 

hionreef

New member
I tested the handheld and it calibrates fine too - thats what is odd
Ill try checking a glass of tankwater and see if that makes a difference

thanks
 

xia

New member
Has the temp of the calibration fluid been accounted for? Should try to make it the same as that of the tank water.
 
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