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Ph probe gone bad?

Posted: Fri Jul 05, 2013 5:45 am
by topjimmy
Greetings all. I think that my Ph probe has gone on the blink. I have noticed a constant fall in PH for some time now. As of this morning it is reading around 3. So either I have a tank full of OJ, or there is a problem with the probe. I just re calibrated it last week. A look at the internal mem spots for ph gives me a 848 for PH 10 and 528 for PH 7.

I suppose that the problem could be electronic interference, but I'm not sure. I'll test a sample of water outside the tank tonight and see what could be going on.

Anyone else ever have a similar problem?

Re: Ph probe gone bad?

Posted: Fri Jul 05, 2013 9:53 am
by Piper
I had a float switch go bad that caused the same problem. Check that in addition to stray voltage from other devices.

~Charlie

Re: Ph probe gone bad?

Posted: Fri Jul 05, 2013 10:10 am
by rossbryant1956
I am currently working this issue as well, not only ph probe but my ph expansion unit. See my post http://forum.reefangel.com/viewtopic.php?f=17&t=3507 for more details.

Roberto there are a lot of people complaining about this right now...Can we have that many dying probes at one time?

Re: Ph probe gone bad?

Posted: Fri Jul 05, 2013 2:00 pm
by rimai
Not sure.
There hasn't been any change in the libs for ph as far as I can remember.

Re: Ph probe gone bad?

Posted: Sat Jul 06, 2013 6:58 pm
by topjimmy
well it's been in a cup of tank water all day,it reports pH as 6.9 I have a Hannah pH pen in the same cup, it reports 8.1. Do the pH probes fail a lot?

Re: Ph probe gone bad?

Posted: Mon Jul 08, 2013 5:07 pm
by JoshSD
Which device are you using to read the data from the probe? The display, or are you getting the low readings from a client application?

I did have a similar problem with an intermittent ph low alarm being sent to my email from the Windows client. I still got that intermittent alarm with the probe in a cup of tank water, and restarting the client app made it stop.

Re: Ph probe gone bad?

Posted: Tue Jul 09, 2013 5:18 am
by topjimmy
The reading is the same on screen and from the portal.

Re: Ph probe gone bad?

Posted: Tue Jul 09, 2013 8:28 am
by rimai
Is the bulb still intact?
Did you try cleaning it with acidic solution? Like white vinegar or diluted muriatic acid?
Did you check if the BNC connector is clean and free of any corrosion?

Re: Ph probe gone bad?

Posted: Tue Jul 09, 2013 8:31 am
by topjimmy
1)Yes
2)Nope, but I will tonight ;)
3)yup

Re: Ph probe gone bad?

Posted: Thu Jul 11, 2013 11:15 am
by fatman
Yeah, mine is bad too. I gave up on it. Need to get a new one and start fresh.

Re: Ph probe gone bad?

Posted: Thu Jul 11, 2013 7:34 pm
by topjimmy
well after a nice soak in vinegar, it still reads way low. guess I'll have to replace it. I wanted the power control module, and the hub so I can control dosers.I guess I'll wait and order it all together.

Re: Ph probe gone bad?

Posted: Thu Jul 11, 2013 10:05 pm
by fish76
For those that have had problems with their probe, how old are they?

Re: Ph probe gone bad?

Posted: Fri Jul 12, 2013 5:06 am
by topjimmy
Mine is probably a year or two old, I don't remember when I bought the RA.

Re: Ph probe gone bad?

Posted: Fri Jul 12, 2013 5:27 am
by lnevo
So to add in to all the ph problems, my ph probe has started to drop as well, been running fine since the last RMA when we had a bad batch of probes. I got an alert last night at 7.7 and as of this morning it's at 7.44. I did an API test and got 7.8 so I know it's not the tank at least. Will try a vinegar bath followed by out of tank test to see...

Re: Ph probe gone bad?

Posted: Fri Jul 12, 2013 5:40 am
by topjimmy
Group Buy!

:lol:

Re: Ph probe gone bad?

Posted: Fri Jul 12, 2013 5:57 am
by lnevo
I'm wondering if it just that the probes are getting older? BRS now has there own brand of probe. It's under $30 but they also have a lab grade at close to $60. Considering just buying a new one...need some more Rox Carbon anyway :)

http://www.all-about-ph.com/ph-probe.html

Expected working life of your pH electrode

The lifetime of your pH electrode is heavily dependent on the application, and how you maintain it. A well-maintained pH electrode will function for 6 to 12 months in most typical applications.

http://www.all-about-ph.com/ph-probes.html

Typical symptoms of an aging probe


• Response will become slower (increase in gel layer resistance).

• During calibration, you will observe an increasing zero point offset and a declining slope value.

• As the probe aging process continues you will need to calibrate more frequently.

• Finally, erratic readings. Now it's definitely time to replace your pH sensor.

Re: Ph probe gone bad?

Posted: Fri Jul 12, 2013 6:04 am
by topjimmy
I was looking at that one from BRS too. Not to sure I really need the precision of a lab grade instrument. I expect the life expectancy is the same.

Re: Ph probe gone bad?

Posted: Fri Jul 12, 2013 6:09 am
by rossbryant1956
I was a poster earlier in this discussion with much the same problems. During my recent re-wire, re-build I pulled everything apart, cleaned my probes, re-calibrated, etc. Still read low. Tried another probe (newer, hardly used) and all is now well.

My previous probe was AT LEAST 6-12 months old, so perhaps Lee's post above bears thought. I also saw the BRS post on lab-grade probes...I wonder what the expected life of those would be? Not sure it is worth twice the price if the life-span is the same.

Other thoughts welcome.

Re: Ph probe gone bad?

Posted: Fri Jul 12, 2013 7:33 am
by lnevo
Going back through my messages, my RMA was in late October so I've been using this probe for just about 9 months. ph is down to 7.42 now, it had dropped as low as 7.38. I think a recalibration may help to some extent. If the probe is reaching its end of life, then based on what I posted above, it won't help for much. Good point Ross on the lab grade probe. It does sound so nice though :)

Re: Ph probe gone bad?

Posted: Mon Jul 22, 2013 11:02 am
by topjimmy
Ok, so I ordered a new PH probe. I have not calibrated it yet, but I continue to get PH readings in the 3's. Last time I calibrated though was with the old meter, I suppose that could be an issue. When I first installed it it read in the mid to high 7's, it has over the last 3 days continuously dropped.

Got to try and find some solution locally.

Re: Ph probe gone bad?

Posted: Tue Jul 23, 2013 9:47 am
by topjimmy
A little update. I was having a problem with my Jebo pump, It seemed to lock up once in a while and not be as strong as it used to be. So I took it out to clean it, and lo and behold, PH jumps up. Not to a normal range, but not a 2 or 3 either. I assume the pump was causing some sort of electrical interference.

On a side note, can you do warranty returns on WP-40's? ;)

Re: Ph probe gone bad?

Posted: Tue Jul 23, 2013 9:59 am
by rimai
Looks like you got stray voltage coming from the pump.
You can contact the manufacturer directly for warranty on their pumps: info@jebao.com

Re: Ph probe gone bad?

Posted: Thu Jul 25, 2013 5:56 am
by topjimmy
So much for that theory. PH back to showing 4

Re: Ph probe gone bad?

Posted: Thu Jul 25, 2013 8:29 am
by rimai
What kind of readings do you get when you place the probe in a cup of tank water?

Re: Ph probe gone bad?

Posted: Thu Jul 25, 2013 9:55 am
by topjimmy
I'll try that tonight, and report back. I know when I did it with the old probe, it did not seem to matter.

Re: Ph probe gone bad?

Posted: Mon Aug 05, 2013 6:42 am
by daniella3d
same here, my ph keep getting lower and lower. This morning it was at 6.3, so I know it's not right. I recalibrated it with fluid 7 and 10 2 days ago and it returned to normal for a short while but it has since keep getting lower and lower. Last night was a real big drop. If that was right I think all my corals would be dead this morning with such low PH.

I am on my second probe since I bought the controller, not even a year ago. I think that's enough.

Re: Ph probe gone bad?

Posted: Mon Aug 05, 2013 10:07 am
by Piper
daniella3d wrote:same here, my ph keep getting lower and lower. This morning it was at 6.3, so I know it's not right. I recalibrated it with fluid 7 and 10 2 days ago and it returned to normal for a short while but it has since keep getting lower and lower. Last night was a real big drop. If that was right I think all my corals would be dead this morning with such low PH.

I am on my second probe since I bought the controller, not even a year ago. I think that's enough.
Sound like stray voltage. What pH do you get when you put the probe in a cup of tank water isolated from the tank?

~Charlie

Re: Ph probe gone bad?

Posted: Fri Aug 09, 2013 6:10 am
by ufgators2k
daniella3d wrote:same here, my ph keep getting lower and lower. This morning it was at 6.3, so I know it's not right. I recalibrated it with fluid 7 and 10 2 days ago and it returned to normal for a short while but it has since keep getting lower and lower. Last night was a real big drop. If that was right I think all my corals would be dead this morning with such low PH.

I am on my second probe since I bought the controller, not even a year ago. I think that's enough.
I also have had that problem with the pH getting lower and lower over time, usually less than 4 weeks. I recalibrate it with the 7 and 10 solution but over that period I can watch my pH slide about .02-.03 per day. I run kalk in my ATO water so I know my water isn't at 7.77 pH, that's when I know to recalibrate.

My probe is about 3 months old.

Re: Ph probe gone bad?

Posted: Fri Aug 09, 2013 6:25 am
by lnevo
It is either stray voltage or a bad probe. I replaced my probe with a pinpoint and am doing much better. It was between that one and the brs value one but that one had bad reviews.

Re: Ph probe gone bad?

Posted: Fri Aug 09, 2013 6:53 am
by ufgators2k
lnevo wrote:It is either stray voltage or a bad probe. I replaced my probe with a pinpoint and am doing much better. It was between that one and the brs value one but that one had bad reviews.
I tested to see if I had a stray voltage by removing some water from the tank and testing it with the probe. It read the same with +/- 0.01, both before and after calibration. Where did you get your replacement probe?