Are Hanna Checkers The Gold Standard In Hobby Grade Test Kits?

[Dan_P]

I like to track my growth and color with pics at least every other week lol.

Have you strung the growth pictures together in a video for time lapse view? That would be awesome!

 

[GARRIGA]

Point of reference. Some used API nitrate reagent with their Hanna checkers when their reagent was scare along with I know one auto tester uses API as an option therefore user error may be highly involved in reefers getting unexpected results. Don’t blame GM if you’re a bad driver being the point.

 

[Troylee]

Have you strung the growth pictures together in a video for time lapse view? That would be awesome!

I haven’t but I did post my short cake in one of the photo contest.. I’d have to figure out how to make a video lol. It was a time lapse thingy.

 

[taricha]

Thank you for your very detailed response! This thread was started because I noticed Reefers consistently saying that their (other brand) test kit is off because the Hanna Checker reads differently. Have you, @taricha, or @Dan_P done an experiment to test how much you can vary the shake time, reagent amount, or water sample amount of Hanna Checkers and still get readings consistent with their margin of error? (In other words, mess it up on purpose.) There are some that believe that every reagent granule, ml, and second are critical for accurate testing with them.

@Dan_P mentioned how he checked shorting some PO4 reagent.

Rick tested under-shaking nitrate tests (hanna and Red Sea)

TABLE 1

CHART 1
​

The reference in Method 4 to the Auto-Shaker can be seen in the link below. I have been using this shaker for quite a while now and it does a good job…a bit noisy but very helpful. https://www.youtube.com/watch?v=sBlGgNaLMq8

I did a check of reagent amounts with NO3. I found that I could pour the NO3 packet into two piles that looked the same to the eyeball (scale says the piles were within 10%) and the results would be essentially identical with each pile.....



I also went lower using a salifert 0.05mL spoon of NO3 reagent, so I could split a packet into 4, but the variation gets larger, and the process is fiddly and messy. not worth it for me.



And here's where @gbroadbridge tried over/undershooting the sample volume purposely.

So I performed the experiment with some photos.

I took about 100ml of tank water and performed a Phosphate test on 3 samples using a Hanna HI774 ULR Phosphate checker.

The test procedure was conducted exactly as instructed by the user manual.

The three sample sizes were 9ml, 10ml, and 11ml using a calibrated micropipette.

Sample Result

9ml 0.05ppm
10ml 0.06ppm
11ml 0.06ppm

So I think it is pretty safe to say that in the range where most folks like to keep their Phosphate level a variation of +/- 10% in the size of the sample has no material effect on the result.

All results were within the stated uncertainty of the instrument.

I did not performs any tests that would identify any non linearity at higher levels of phosphate.

I think it's proven unnecessary to be any more accurate than to simply fill the cuvette to the marked line.



10ml sample



9ml sample




11ml Sample

The overall picture is that these hanna tests (the most popular ones - NO3 and PO4) seem resilient to these sorts of small technique errors.

Some hanna tests, like Ca can be really unforgiving of errors.

 

[Reefer Matt]

@Dan_P mentioned how he checked shorting some PO4 reagent.

Rick tested under-shaking nitrate tests (hanna and Red Sea)



I did a check of reagent amounts with NO3. I found that I could pour the NO3 packet into two piles that looked the same to the eyeball (scale says the piles were within 10%) and the results would be essentially identical with each pile.....



I also went lower using a salifert 0.05mL spoon of NO3 reagent, so I could split a packet into 4, but the variation gets larger, and the process is fiddly and messy. not worth it for me.



And here's where @gbroadbridge tried over/undershooting the sample volume purposely.



The overall picture is that these hanna tests (the most popular ones - NO3 and PO4) seem resilient to these sorts of small technique errors.

Some hanna tests, like Ca can be really unforgiving of errors.

Thank you very much for that! With the exception of the calcium test, it seems to me that some Reefers overthink the use of some Hanna Checkers and what is actually required to get a good test result from them.

 

[areefer01]

Thank you very much for that! With the exception of the calcium test, it seems to me that some Reefers overthink the use of some Hanna Checkers and what is actually required to get a good test result from them.

I don't think that is the case at all. Honestly it just goes to show how two hobbyist can use the same piece of gear and have different experiences. How much of my results or @taricha are hobbyist consistency? Note - not questioning results are assessment but rather showing how two users of a same tester have different experiences.

I think at the end of the day hobbyist learn over time correlation between display look and feel and measurement results.

 

[GARRIGA]

Outside the few needing NASA level precision. Rather easy to visually grasp 20 ppm acceptable (between yellow and first red) vs yellow bottomed out to wine red better call Sal. If one can't appreciate colors then how do they perceive powder blues and purple tangs and all the other colorful additions and why fresh can no longer satisfy their thirst. Perhaps shades and if that's the case then that shade in the vial likely matches one of the shades on that chart.

Phosphates also again give reasonable results for those not skirting Stick level adhesion to 0.03-0.09. At least for me, can determine results between 0 and 0.25 ppm yet Richard Ross doesn't break sweat until north of 0.9.

WWC maintains nitrates around 20-25 ppm including Sticks. Do most of us even need gold standard or will silver suffice because it seems every newb to the hobby quotes either obtaining these lofty goals or asking for help first sign their hobby grade test kits deviate. Truth be told. They probably forgot to shake

 

[Dan_P]

@Dan_P mentioned how he checked shorting some PO4 reagent.

Rick tested under-shaking nitrate tests (hanna and Red Sea)



I did a check of reagent amounts with NO3. I found that I could pour the NO3 packet into two piles that looked the same to the eyeball (scale says the piles were within 10%) and the results would be essentially identical with each pile.....



I also went lower using a salifert 0.05mL spoon of NO3 reagent, so I could split a packet into 4, but the variation gets larger, and the process is fiddly and messy. not worth it for me.



And here's where @gbroadbridge tried over/undershooting the sample volume purposely.



The overall picture is that these hanna tests (the most popular ones - NO3 and PO4) seem resilient to these sorts of small technique errors.

Some hanna tests, like Ca can be really unforgiving of errors.

Thought of one more thing we put a great amount of time into that highlights the usefulness and reliability of the Checker photometer. We used the Checkers to measure the color intensity for many different hobby kits. We also studied turbidity and I think we dabbled with measuring chlorophyll extracts. Potentially irrelevant to the current topic but always good to point out that the photometers are serious analytical devices, with limits of course.

 

[Dan_P]

I think at the end of the day hobbyist learn over time correlation between display look and feel and measurement results.

AI kinda works this way which makes understanding why and how it works frustrating. For human’s such inscrutable thinking is related to implicit knowledge, the stuff we know how to do but can’t explain how we do it or worse, we don’t even realize we are doing something important.

There is another perspective to consider. Very few aquarists put error bars on their measurement, nor perform a t-test to determine if the measurement that differs from that last one is just a result of variation, noise in the data.

 

[areefer01]

AI kinda works this way which makes understanding why and how it works frustrating. For human’s such inscrutable thinking is related to implicit knowledge, the stuff we know how to do but can’t explain how we do it or worse, we don’t even realize we are doing something important.

There is another perspective to consider. Very few aquarists put error bars on their measurement, nor perform a t-test to determine if the measurement that differs from that last one is just a result of variation, noise in the data.

Of course. Median, std dev, 9(x)th percentile, and more put numbers into perspective.