PH Calibration Fluids

[Kyle Sicard]

Hey all,
I'm new to controllers but when I originally calibrated my PH probe I didn't realize that dipping the probe into ph 7.0 then into ph 9.0 without cleaning the probe would matter. And then after that I was recalibrating them again and someone recommended to dip the probe in freshwater before dipping into the calibration fluids so I did that as well.

Now I'm reading off of GHL's downloads that you are suppose to dry the probe before inserting into either calibration fluid. I believe my PH probe is reading a little low and was wondering if maybe the contamination of the fluids is the issue? I didn't think tiny amounts of the liquids would it affect it, but now I'm wondering if that's the reason for why my probe reads a bit low.

I know you can adjust the ph reading in GCC, but I don't have a reliable way to test my PH currently that I could use for the adjustment setting.

 

[Lasse]

Reading little low - compared with what?

Dry it or not between the calibration fluids? I have been used pH meters since the beginning of 1983. Never have dry the electrode - only have rinse with RO water and shake the electrode from excess water between the calibration fluids. I also always check the little white point that you can see it you turn the electrode upside down. If it is coloured – rinse it carefully (carefully) with a soft tooth brusch

I normally use a little sample of calibration fluids in a separate 10 ml container. The level should be a couple of millimetres over the notches in the plastic round the glass tip. The glass tip and the flat bottom of the electrode should be in the calibration fluid. I dispatch the fluid after use and calibration check. Then you have calibrate with the two fluids. Rinse the electrode – dip it in the 7 fluid. 6.95 – 7.05 is acceptable. Rinse and dip in the second fluid (9.0). 8.95 – 9.05 is acceptable. Do not be fooled by the second decimal of the measurement, normally, you can´t rely 100 % on it. This is not only for the pH electrodes from GHL – it’s valid for most electrodes that’s not cost a fortune. According to the pH-electrodes from GHL – they are among the best I have used. And I have use them in tough environment.

One thing with new electrodes is that they sometimes need to recalibrate them after a week or two. Normally – a recalibration each month is enough. I recalibrate my own electrode after 4 months – the change was in the 0.05 range

When you have calibrate the electrode – trust it even if you colour test says different

Sincerely Lasse

 

[Kyle Sicard]

Thanks for the detailed process. My comparison on being low is just experience with aquariams. I just re calibrated once again, and its still reading my ph in the 7.5 range.

 

[ahiggins]

Reading little low - compared with what?

Dry it or not between the calibration fluids? I have been used pH meters since the beginning of 1983. Never have dry the electrode - only have rinse with RO water and shake the electrode from excess water between the calibration fluids. I also always check the little white point that you can see it you turn the electrode upside down. If it is coloured – rinse it carefully (carefully) with a soft tooth brusch

I normally use a little sample of calibration fluids in a separate 10 ml container. The level should be a couple of millimetres over the notches in the plastic round the glass tip. The glass tip and the flat bottom of the electrode should be in the calibration fluid. I dispatch the fluid after use and calibration check. Then you have calibrate with the two fluids. Rinse the electrode – dip it in the 7 fluid. 6.95 – 7.05 is acceptable. Rinse and dip in the second fluid (9.0). 8.95 – 9.05 is acceptable. Do not be fooled by the second decimal of the measurement, normally, you can´t rely 100 % on it. This is not only for the pH electrodes from GHL – it’s valid for most electrodes that’s not cost a fortune. According to the pH-electrodes from GHL – they are among the best I have used. And I have use them in tough environment.

One thing with new electrodes is that they sometimes need to recalibrate them after a week or two. Normally – a recalibration each month is enough. I recalibrate my own electrode after 4 months – the change was in the 0.05 range

When you have calibrate the electrode – trust it even if you colour test says different

Sincerely Lasse

I don't have one for my tank but the ones I use in my lab are calibrated every other week and each week I do a "check cal" which is just checking the probe with cal solution to verify it's running correctly. But yes, I totally agree with lasse-it's not needed to do all the excessive steps. Rinse and shake

 

[BCSreef]

I don't have one for my tank but the ones I use in my lab are calibrated every other week and each week I do a "check cal" which is just checking the probe with cal solution to verify it's running correctly. But yes, I totally agree with lasse-it's not needed to do all the excessive steps. Rinse and shake

At the lab and at home, I always rinsed with RO/DI or distilled, then shake off the excess between calibration fluids. I calibrate probes every 1-3 months at home. Far more often at lab.

Bob

 

[Kyle Sicard]

Thanks for the input guys. Looks like my PH is reading more adjusted now, a reading in the 7.5 range was just too low but I'm getting a more stable reading now that I just did the rinse and shake method.

 

[BCSreef]

I also do what Lasse suggests. I don't insert the probes into the bottles of calibration fluids to avoids cantamination. I pour 10-15 ml into a shot glass and throw it away when done. The heavy bottom of the shot glass keeps them from tipping over with probe in place. Plus you can do a shot of your favorite spirit to celebrate successful calibrations

Bob

 

[BCSreef]

I also buy the pH fluids in 500 ml bottles at ~$20.00 for a set of 3 bottles of pH 4, 7, & 10.

Bob

 

[george7523]

why dont ghl include the ph9 calibration fluid in the starter pack ? according to their manual, it is what's needed for salt water , not ph4. lame

 

[Ditto]

@george7523 - I see you posted on 3 different posts about the same thing. Have you reached out to them to are maybe they included the wrong package and let them know? @Vinny@GHLUSA are you guys aware of this?

 

[Lasse]

why dont ghl include the ph9 calibration fluid in the starter pack ? according to their manual, it is what's needed for salt water , not ph4. lame

All starter packs for P3 and P4 I have seen include pH 4, 7 and 9 standards. However - the KH unit does only content 4 and 7 because the probe should only be calibrated between 4 and 7.

Sincerely Lasse

 

[Vinny@GHLUSA]

why dont ghl include the ph9 calibration fluid in the starter pack ? according to their manual, it is what's needed for salt water , not ph4. lame

Simple. Because the Starter Set is geared towards the freshwater community. If you look closely at the set photo, you'll notice freshwater plants on the image...you can also see the fluid bottles in the same photo. It wouldn't make sense to offer SW range fluids for a product that shows a FW image...

Compare that to the set photo of the Mega Set which has a saltwater image on it.

 

[george7523]

I guess when i purchased the starter pack, I forgot to look closely at the background packaging pictures. Instead I was doing research on online forums and youtube, where 99% of people uses it for saltwater setups. sure you can hide behind that argument. realistically we all know controllers such as profilux and apex are used by saltwater setups. Who uses a controller for freshwater tanks ? maybe 1% of aquarist out there. google profilux and see what you get. on youtube, only 1 video shows freshwater setup. And that one is provided by ghl, not bought by themselves. But i'm sure you know this already. but ok, sure it's geared towards freshwater. for a package that cost $800, by including a ph9 solution which probably cost less then $2, ghl can also make it "officially" gear toward saltwater as well. what a huge oversight and a petty exclusion to save little money and cost buyers huge inconvenience. If i already spent $800 on a starter pack, i sure wouldnt care if i had to pay $8 extra on a ph9 solution. but it sure is an inconvenience and irritation to have to order it separately and wait a week later for it to arrive. it makes me even less confident in the brand. btw, i have 9 freshwater tanks. none of them have controllers.

 

[Lasse]

Do not forget that GHL is a German brand. The aquarium computer market is different in Europe compared with US. It is more common with using computers for freshwater here than in the US. The 4E has no salinity or redox connections - IMO - it clearly oriented to the freshwater part of the hobby.

Sincerely Lasse

 

[george7523]

point taken Lasse, thanks. The starter pack profilux unit sold by BRS is identical to the mega pack unit and does have connections to salinity and redox (total of 4 BNC connections). It just doesn't come with those two probes. I never been to europe myself so I rely on the internet and youtube for my research. Base on those 2 resources, it's my finding that a good majority if not all uses profilux for saltwater. In you experience, how often do you encounter people or any online posting where the user uses profilux for freshwater ? Online research also seems to indicate salinity probe is often not very accurate due to different environmental factors. I'm not sure about the redox probe. research seems to indicate it's not very useful. But i probably just don't know enough about it. Maybe you can shed some light on how to use the redox probe. Which leaves temperature and Ph probe that will be alot more useful and attractive for reefers. so yeah, I respectfully disagree with the opinion that starter pack is more for freshwater hobbist. try googling "profilux freshwater" vs "profilux saltwater". the search result should speak for itself.