what makes a hanna checker fail?

[smitten with ocean life]

good morning all! i was wondering if anyone could give me some tips on the hanna checkers. i recently ended up buying a pretty spendy device because of my alk checker. it had been very consistent for a long time then started showing me dropping numbers. long story short, i got a device to stabilize my alkalinity, only to find out my alk has been stable- my hanna checker isnt! so what to do with the checker? toss it? or is there a way to reset it?

 

[Dan_P]

good morning all! i was wondering if anyone could give me some tips on the hanna checkers. i recently ended up buying a pretty spendy device because of my alk checker. it had been very consistent for a long time then started showing me dropping numbers. long story short, i got a device to stabilize my alkalinity, only to find out my alk has been stable- my hanna checker isnt! so what to do with the checker? toss it? or is there a way to reset it?

I am interested in hearing more about how you proved the Checker was drifting.

 

[Science/G]

I would replace the batteries and invest in some new reagent and vials and give it a go again.

 

[smitten with ocean life]

ok ill try that. thanks! it shows full battery but ill switch them out. the reagant just expired so who knows. wasnt sure how fast you needed to chuck it. i tried a different vial though to no avail.
it had been showing right around 9 for quite awhile. then seemed like every week the number dropped some more. currently it says 3! so i got a kh guardian and it showed 9 and still has never needed to dose.! ordered a salifert and it also shows 9.

 

[BriDroid]

Hanna also sells calibration checkers. They’re not crazy expensive, I’ve often considered getting some for my checkers. That would be an easy way to determine if they’re reading correctly.

 

[AydenLincoln]

Battery switch, calibration, and ensure enough lighting is in the room!

 

[JayM]

good morning all! i was wondering if anyone could give me some tips on the hanna checkers. i recently ended up buying a pretty spendy device because of my alk checker. it had been very consistent for a long time then started showing me dropping numbers. long story short, i got a device to stabilize my alkalinity, only to find out my alk has been stable- my hanna checker isnt! so what to do with the checker? toss it? or is there a way to reset it?

Any chance that there’s something inside blocking the light and/or the sensor?
Though I’d imagine that would give you an artificially high reading.

 

[smitten with ocean life]

well ill def check! i always do it in the same spot so i doubt lighting factored in but ill give it a closer once over!

 

[Randy Holmes-Farley Verified Community Expert]

Hanna also sells calibration checkers. They’re not crazy expensive, I’ve often considered getting some for my checkers. That would be an easy way to determine if they’re reading correctly.

But only the electronics, they do not check your vials, technique, reagents, etc.

 

[Randy Holmes-Farley Verified Community Expert]

Miami says he is very careful in his Hanna technique. I'm sure he can weigh in:

@Miami Reef

 

[Science/G]

Hanna also sells calibration checkers. They’re not crazy expensive, I’ve often considered getting some for my checkers. That would be an easy way to determine if they’re reading correctly.

Good call!

 

[Science/G]

Ensure the position of the vials is the same for C1 and C2

 

[Miami Reef]

I don’t have much experience with the Hanna alk tester. It’s hard to quantify if the checker is wrong or the reagent is; the latter is known to drift for some folks.

I significantly prefer titration methods for alkalinity.

The Hanna Alk kit fails verification—DIY Alk standards won’t work with it. You’re basically just trusting it works unless you compare it to a titration kit.

 

[Rick Mathew]

good morning all! i was wondering if anyone could give me some tips on the hanna checkers. i recently ended up buying a pretty spendy device because of my alk checker. it had been very consistent for a long time then started showing me dropping numbers. long story short, i got a device to stabilize my alkalinity, only to find out my alk has been stable- my hanna checker isnt! so what to do with the checker? toss it? or is there a way to reset it?

If you really would like to validate the checker you might consider creating a set of Alk standards ...Like 7,8,9,10dKH and doing the measurement with them...It should give you a good idea if your meter is off. This is essentially what you would do with the Hanna Calibration Checker except you check it at 3 or 4 points rather than one...This is a actually better method for picking up any possible LED degradation or wavelength shift..

Listed below are some of the more likely issues that could cause the issue (per ChatGPT)...I am sure there are others but I would start with the measurement of standard solutions at your anticipated measurement range...Say 7-10dKH

• LED Degradation or Shift: The LED inside the checker that provides the light source may degrade over time or shift slightly in wavelength output.
• Sensor Issues: The photodetector could become less sensitive or misaligned, affecting how it "sees" the color change.
• Firmware/Software Glitches: If the device has internal calibration tables or software-based wavelength compensation, a bug or internal memory issue could affect it.
• Physical Damage or Contamination: Scratches on the lens, residue inside the chamber, or moisture can cause refraction or scattering that impacts wavelength detection.
• Power Supply Irregularities: Low or inconsistent battery power can affect the stability of the light source.

Or you can use a titration method as Miami Reef suggested as a referee

Just my thoughts

 

[BryanM]

I'm pretty consistent with how I test, rinse vial with rodi twice between tests, etc.

I do not know for sure, but I think most of this comes down to the consistency of the reagents. I often get an odd ball result, and I'll retest and it will be fine.

 

[Miami Reef]

I often get an odd ball result, and I'll retest and it will be

Does the oddball test higher or lower than expected?

 

[BryanM]

Does the oddball test higher or lower than expected?

Both actually, but if there's a trend I believe it is higher.

But when I say oddball, I know for a few months my nitrates are around 15-20, and I'll either get a test at zero, or off the charts high. Its obviously no where near reality. I test again and get a normal result.

 

[smitten with ocean life]

well ive retested multiple times and it consistently gives me a number in the 3s or 4s

 

[BryanM]

well ive retested multiple times and it consistently gives me a number in the 3s or 4s

In the case of the alk tester, I know my last few tests with the end of my bottle of reagent all tested low.

I got new reagent and tests started to make sense again.

 

[Reefer Matt]

There’s no way to reset it. You can check its accuracy with the standard solutions, but either the vials, reagent, technique, or tester itself are the cause for odd readings. I swirl the reagent bottle before every use to ensure it is a homogenized mixture without excessive air introduced. I believe some settling occurs, especially for those who test “once in a while”. If the checker itself is off, there is a one year warranty, and they will send a new one.