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jabel
11/17/2009, 12:44 PM
So I just upgraded from a JR to the III and I transferred over my pH probe and added a new one. The new probe measures my tank pH about 0.14 unit lower than the JR and a 3rd pH meeter. The old probe is even worse measuring about 0.3 units lower than the other two meters. I'm using the same buffers to calibrate all three units and the JR and the 3rd pH meter agree with thier readings. Could this be a problem with the AC III itself?

In case it matters I have the old probe in the ca reactor and the new one in the main tank.

Jeff
jabel
11/17/2009, 08:51 PM
Anyone?
swearint
11/18/2009, 10:57 AM
Can you explain the issue a bit more? If you have calibrated all of the probes in the same buffer solutions (I assume 7.0 and 10.0) then they should read indentically when placed in those solutions. Do they not? Or are they reading differently, after calibration, when placed in the tank? If the latter, then each probe/device may be more or less susceptible to interference in the tank. Have you tried measuring a sample of the tank water outside of the tank, i.e. in a cup?

Todd
jabel
11/18/2009, 02:08 PM
Yes, after callibration the probes/meters all read the same pH of the callibration solutions (7/10). When in the tank they measure the differently. I haven't tried the cup of water so I'll give that a try. What do you mean by interferance?

Thanks for the reply.
swearint
11/18/2009, 02:41 PM
Electrical interference from the various pumps, lights, stray voltage, etc.

Todd
jabel
11/18/2009, 05:17 PM
I didn't have an issue with this using the Jr. Is this something that only affects the acIII?
bullitr
11/18/2009, 05:23 PM
jeff
my apex read 7.78 and my milwake read 8.0.apex calibrated using 7.0 and 10.0 and 7.0 for the milwake. the apex use to read very high 8.4.
jabel
11/18/2009, 05:58 PM
That's what I'm trying to figure out. Is there an issue with the ACIII or not and can it be fixed or is this an acceptable range. I know my tank pH is ok since I have secondary meters to verify, but I'd like the meter that I paid lots of $$ for to be accurate as well. The apex cost even more. Have you figured out what to do?
Jeff