ph reading off

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Civics14
Posts: 95
Joined: Fri Nov 14, 2014 8:27 am

ph reading off

Post by Civics14 »

Ok, so I got the reef angel plus during the bf promo, i just recently set up my tank earlier this month... everything works as it should but my ph is off. Out of the box, it was reading 7.4 - 7.6, which was extremely low. So, I got some calibration fluid (7.0 & 10.0) and now it is reading between 7.8 - 8.0. I have had my water tested at two different local fish stores and bought the API saltwater test myself, and every result shows between 8.0 and 8.2.

So, it looks like, it is off by 0.2. Has anyone else had this problem? I understand that a stray voltage could cause this, but even when I take a cup of water out of the tank and test it in the cup, the readings are the same.

any advice on this?
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Civics14
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Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

I got a voltage meter:
10v from the ph probe
15v from the return pump

from my understanding its normal for the return pump to have stray voltage due to the magnets, but is it normal for the ph probe?
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rimai
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Joined: Fri Mar 18, 2011 6:47 pm

Re: ph reading off

Post by rimai »

When you place the probe in the calibration fluids, did you confirm readings of 7 and 10?
Maybe the calibration is still off.
Roberto.
Civics14
Posts: 95
Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

Ok, just got around to doing this... so i redid the calibration on the ra menu and 7.0 calibration = 512, 10.0 calibration = 795. Not sure what those numbers mean, but that's what it settle on, i left it there for 5 min. after it settled just to be sure.

afterwards, i tested the results on NEW fluid after rinsing the probe in some distilled water
all readings settled and i waited 5 min to be sure:
7.0 fluid read 6.91
10.0 fluid read 10.12

Very weird
rimai wrote:When you place the probe in the calibration fluids, did you confirm readings of 7 and 10?
Maybe the calibration is still off.
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Civics14
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Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

Any help on this Roberto? Not understanding the fluctuation even after calibration.

Also I tried the tip about adding the lines after Reefangel.int and it did nothing:

ReefAngel.PHMin=512;
ReefAngel.PHMax=795;
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rimai
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Re: ph reading off

Post by rimai »

When you finished the calibration, was era showing ph10?
Roberto.
Civics14
Posts: 95
Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

no, i can't recall what screen it returned to, but definitely didn't show any errors.
rimai wrote:When you finished the calibration, was era showing ph10?
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Civics14
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Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

Anyone have any advice on this? I would like to be able to get the correct PH reading for once
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lnevo
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Re: ph reading off

Post by lnevo »

I would try a different probe. They really dont as long as people would think
rimai
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Joined: Fri Mar 18, 2011 6:47 pm

Re: ph reading off

Post by rimai »

I'm thinking the problem was the calibration.
If you go into calibration mode with the probe in your tank, what value do you get?
Roberto.
Civics14
Posts: 95
Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

lnevo wrote:I would try a different probe. They really dont as long as people would think
I just bought the RA+ w/ WiFi during the Thanksgiving Sale a few months ago. And I just put it to use starting Jan. 2nd. So it hasn't even been a month since I actually even used it.
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Civics14
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Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

rimai wrote:I'm thinking the problem was the calibration.
If you go into calibration mode with the probe in your tank, what value do you get?
I'll get this # when I get home in a few hours. Hopefully we can get to the bottom of this.
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Civics14
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Re: ph reading off

Post by Civics14 »

Ph 7.93, calibration menu shows 600
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rimai
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Re: ph reading off

Post by rimai »

I think your calibration numbers are off by around 12
Try adding this to setup() after ReefAngel.Init()

Code: Select all

ReefAngel.PHMin=500;
ReefAngel.PHMax=783;
Roberto.
Civics14
Posts: 95
Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

rimai wrote:I think your calibration numbers are off by around 12
Try adding this to setup() after ReefAngel.Init()

Code: Select all

ReefAngel.PHMin=500;
ReefAngel.PHMax=783;
Thanks Roberto, now its reading 8.04.
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Civics14
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Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

Hi Roberto,

My PH reading went crazy this morning, at 6:20am it showed a 2.48PH!! Nothing has changed. Why am I having such a difficult time with my ph reading??
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Civics14
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Re: ph reading off

Post by Civics14 »

Ok, never mind, found out my return pump is causing it all of a sudden, which is really strange because nothing has changed with it. Why all of a sudden my return pump would leak so much stray voltage to cause such a problem
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Civics14
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Joined: Fri Nov 14, 2014 8:27 am

Re: ph reading off

Post by Civics14 »

Actually, I got a hold of a voltage meter and did some more testing. It was not my return pump like I assumed, it was the ATO switch... I haven't even had this running for 2 months and it has already went bad on me. Is that normal??
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