Neptune Apex Ph Probe life
 

How long would you expect your Neptune lab grade pH probe last?

I started dosing kalk through my ATO a week and half prior and either through random odds or something else, my pH probe started reading gradually lower levels. I quickly did a water change and the probe didn't change. Using a separate calibrated meter, my pH was fine.

I have to clean mine every 30 days , 14 months seems to work fine except must be clean, but my number goes upwards, not downwards

That will vary a lot, but cleaning and recalibrating every month is a good first guess. Bacterial and algal growth rates vary a lot in our tanks.

if it cannot hold its calibration reading (value of the calibration fluid), then its time to replace.

Not holding calibration is how a probe tells you it has retired and no longer wants to work. Generally about a year or more.

How old is yours?

I have several standard PH probes that are 4 & 5 years olds do stil working fine. The ones before lasted equally long for me. I have new spares that I have had so long the packing fluid had dried out, I just refilled the proactive caps 2 days ago after soaking them to remove the salt build up on them first.

Just to add to what was said I have found that the need for cleaning can be greatly reduced and the lifespan extended by months if you use a probe holding system that is self contained and only allows water to flow in slowly. Mine is made out of 3" PVC that is flattened on two sides and a PVC hook system glued on. I made a removable top cap and a fixed bottom cap, About a dozen 2mm holes are drilled verticaly on each side and there are large enough holes at the top for the thinner part of the probe to drop down through and fatter part rest down on the top PVC cover.

This container makes the flow rate very slow inside and since no light is getting in, no algae or other crap builds up on the probes. I have found that the faster the flow rate past the probes is the less time they last. So slowing it down has given me almost two years of life per probe. The only one I keep outside of this container is my Oxygen probe.


Rob

i have a probe ph neptune and have 9 years ago.

I replaced my original Lab-grade APEX pH probe with this industrial process pH sensor which is far more suitable for continuous use in a harsh reef tank environment than a lab-grade electrode designed for light intermittent use: https://sensorex.com/product/s272cd-...ess-ph-sensor/
https://sensorex.com/wp-content/uplo...HI-RES_RGB.jpg
Due to its flat sensing surface, it is also easier to clean.
It also comes with a manufacturing date which is kind of important since sealed combination pH electrodes start aging from the day of their manufacture.

This one is of the same basic design but identical in size to the APEX probe. It is also no more expensive than the APEX Lab-grade pH electrode:
https://www.mcmaster.com/14775t23
https://www.mcmaster.com/mvA/Content...9199061635.png

I just recalibrated all 3 of my PH brobes and realized they are much older than I thought. I have only ever replaced two PH probe in 27 or so years of reef keeping. I am still using a Aquacontroller 2 and a 3 Pro. I have had both for 20 + years. One is still using the original PH probe. My apex I picked up used 3 years ago or so and is still using the original PH probe. Non of these 3 probes had been calibrated in years and they were not far off after all this time. I did recently setup mycalcium reactor after not using it for 4 years and had to replace that probe, making it the second one ever. I could never figure out why a buddy was constantly changing his probes every 3 months. My tanks can’t be that different than other peoples.

:eek1::eek1: Huh :eek1::eek1:


Are you and Laverda only using them to test water samples? I have never seen a continually used probe last that long.


Rob

How long do you get out of one of these probes?

Mine have been in continues use except the on that was for my calcium reactor. I sat unused for about 4-5 years. It was in fluid when stored but had dried up. I tried to revive it without any luck. The probe I replaced it with was new but had dried out from being in storage from at least 2013. That was the date on the calibration packets stored with it. I revived it without any problems by just leaving it in my sump a few days before calibrating it.

I'm only using it for a few months so I have no long term data yet. But just from the geometry, it is easier to maintain and clean. And unlike a lab electrode, it is actually designed for continuous use in dirty water.

The factor that makes a pH probe "wear out" and also require re-calibration actually involves the internal fill solution. Inside the electrode there is a gel solution of silver-silver chloride which has liquid contact with the water sample via reference junction(s). Over the course of time the internal fill solution will become more dilute, usually at a steady rate which could necessitate re-calibration. At some point in time the internal fill solution will become so diluted that the calibration is no longer possible, easy or responsive thus necessitating replacement.
Personally whenever I have seen probes used for very extended periods it is usually the case that the reading "looks ok" and verification is not done. Even a broken clock (analog of course) is correct twice a day. Verification for pH electronics would be 2 point re-calibration to determine it is reading both properly and quickly.

All I can say is my probes calibrated with out any issue using 7 and 10 calibration fluids and verified as right on after calibration again with 7 and 10 fluids.

Just out of curiosity how frequently do you re-calibrate with fresh fluids?

I had not calibrated for 2-3 years before I did it recently. After calibration, my numbers were not significantly different.