pH toooooo low!

[GoVols]

yeahhh... it seems silly at first, but with a 10-year warranty; when you start to do the math it makes sense over the long haul. It gets even better when comparing electrical savings against more traditional AC pumps.

While it may not be made of gold, it's also not made of cheap materials that will eventually corrode and leach in your tank either. I have a box of bulged, split and rusty VorTechs for example. Imagine what's happening with less expensive circulating pumps?

Back to Dennis' original topic: 3/8"-18 NPT tap arrived today. Tomorrow's project is to replump the skimmer's intake.

Who knew this thread would turn into a tool buying opportunity!

M

M,
I almost bought the Abyzz A100 DC, but I got a GEO cal reactor instead.

Talked to Klaus at Royal Exclusiv and they have new DC's in the works, and they are beta testing them, right now.

Freddie

 

[bubbaque]

Dennis, watch the temp of the cup. Temp will affect the ph reading also

 

[Want2BS8ed]

M,
I almost bought the Abyzz A100 DC, but I got a GEO cal reactor instead.

Talked to Klaus at Royal Exclusiv and they have new DC's in the works, and they are beta testing them, right now.

Freddie

Hear that! Gotta do what you gotta do... good to hear Royal is working on some new DC pumps. Hopefully the competition at the top end of the market will bring prices down.

Meanwhile, the replumb on the skimmer intake is done. Hopefully the picture below makes sense.

It will take about 3 weeks to see if it made an appreciable difference in the life of the media, but I'm pleased with how it turned out.

M

 

[Brew12]

I'm still baffled by this. It just isn't making sense in my pea brain. Its almost like it isn't a pH sensor plugged into the pH port.

 

[GoVols]

Meanwhile, the replumb on the skimmer intake is done. Hopefully the picture below makes sense.

It will take about 3 weeks to see if it made an appreciable difference in the life of the media, but I'm pleased with how it turned out.

M

Looks great!!!

 

[d2mini]

UPDATE:
The cup was outside this morning with a small pump circulating the water from 8am to 12 noon.
Temps were about 67-68 when I took it inside and shoved the pH probe in there.
The pH topped out at 7.85

I put the cup back outside and will retry later this evening.

Anyone know what kind of effect the 10 degree difference in water would have had?
Still seems pretty low to me though.

 

[Brew12]

UPDATE:
The cup was outside this morning with a small pump circulating the water from 8am to 12 noon.
Temps were about 67-68 when I took it inside and shoved the pH probe in there.
The pH topped out at 7.85

I put the cup back outside and will retry later this evening.

Anyone know what kind of effect the 10 degree difference in water would have had?
Still seems pretty low to me though.

The temp compensation would be less than 0.1.

You have a pH probe issue.

Edit: Actually, before I put my foot in my mouth with a statement like that... what is the alkalinity of the sample?

 

[Randy Holmes-Farley Verified Community Expert]

The temp effect on measured pH is complicated and is actually caused by different things.

The probe itself varies in its output as a function of temp, and the effect is zero at pH 7.000 and gets larger the farther you are from pH 7. Essentially, the slope of the mv vs pH response changes.

here's a calculator for that part of the effect:

https://www.hamzasreef.com/Contents/Calculators/PhTempCorrection.php

A second effect has to do with how the pH changes the pKa of the main buffers in the solution. In seawater, bicarbonate is the main acid present in the buffer system, and it is a stronger acid as the temp is raised. It's pKa goes from 6.1 at 0 deg C in seawater to 5.7 at 40 deg C in seawater. That pH shift will tend to reduce pH (a measure of H+) as the temp is raised because more HCO3- will ionize to H+ and CO3--. This is part of the reason why there is more precipitation on warm heaters and pump impellers: because carbonate is locally higher than at cooler temps.

 

[d2mini]

Edit: Actually, before I put my foot in my mouth with a statement like that... what is the alkalinity of the sample?

When i took it out of the tank this morning, it was 8.5 dkh

 

[Brew12]

The temp effect on measured pH is complicated and is actually caused by different things.

The probe itself varies in its output as a function of temp, and the effect is zero at pH 7.000 and gets larger the farther you are from pH 7. Essentially, the slope of the mv vs pH response changes.

here's a calculator for that part of the effect:

https://www.hamzasreef.com/Contents/Calculators/PhTempCorrection.php

A second effect has to do with how the pH changes the pKa of the main buffers in the solution. In seawater, bicarbonate is the main acid present in the buffer system, and it is a stronger acid as the temp is raised. It's pKa goes from 6.1 at 0 deg C in seawater to 5.7 at 40 deg C in seawater. That pH shift will tend to reduce pH (a measure of H+) as the temp is raised because more HCO3- will ionize to H+ and CO3--. This is part of the reason why there is more precipitation on warm heaters and pump impellers: because carboante is locally higher than at cooler temps.

Show off!

I'll stick with the less than 0.1

When i took it out of the tank this morning, it was 8.5 dkh

Yup.. pH probe issue.

 

[Potatohead]

Just buy a new probe already lol. You're going to need it eventually anyway.

 

[Brew12]

You use Profilux, right? Is the pH probe you used the one with your Profilux system?
And it calibrates ok?

 

[Want2BS8ed]

durn... you had me when you said it was 68 degrees this morning!

 

[Brew12]

If it is Profilux, take a look at your pH calibration data. Here is mind from myGhL. Your numbers should be fairly similar.

 

[d2mini]

Just buy a new probe already lol. You're going to need it eventually anyway.

This weekend!

You use Profilux, right? Is the pH probe you used the one with your Profilux system?
And it calibrates ok?

Yes, the Profilux seems to calibrate it ok. But this is not an original probe. I think this one was a BRS probe.
Probably a year old this month if it is the one i bought from them.

durn... you had me when you said it was 68 degrees this morning!

It was 54 at 5am and headed to 72 today!
But back to a high of 42 this sunday. ;Nailbiting
I've been miserable all winter.

 

[d2mini]

If it is Profilux, take a look at your pH calibration data. Here is mind from myGhL. Your numbers should be fairly similar.

Huh... never paid attention to that before.
Mine are...
7.0
386
9.0
185

 

[GoVols]

Heck,
We're at 65 degrees in Nashville today, and our town home's windows are up.

 

[Want2BS8ed]

One thing I did pickup from BRS's video on CO2 scrubbing: I purchased a normally closed 120v solenoid valve from McMaster-Carr that is installed in a 3/8" push-fit tee just after the CO2 scrubber. The solenoid is hooked up to my Apex and is set to open when pH hits 8.2. Because there is less restriction without the reactor and media, air is drawn through the open valve, bypassing the CO2 scrubber and saving media. When the pH drops below 8.1, it closes drawing air through the media.

With that much media, I went from just under two weeks to exhaustion to just over three. Not much, but it is a 50% increase and the valve has paid for itself now several times over.

Need to make a quick correction, the McMaster-Carr valve (part #5489T493 w/ 3/8" quick connects) is 24v, not 120v as originally stated.

It's hooked to and controlled through the 24v accessory outlets on Neptune's Apex EB832 energy bar.

Sorry if that caused any confusion.

M

 

[Brew12]

Huh... never paid attention to that before.
Mine are...
7.0
386
9.0
185

That actually looks pretty good as far as spread goes. If you ran with my calibration data your pH would look good!

I just don't understand why your calibrates to a proper ranged spread but reads so low. When you finished calibrating it, did you retest it in the solutions?

 

[d2mini]

That actually looks pretty good as far as spread goes. If you ran with my calibration data your pH would look good!

I just don't understand why your calibrates to a proper ranged spread but reads so low. When you finished calibrating it, did you retest it in the solutions?

No, I did not.