Hanna calcium checker

Centerline · Feb 21, 2017

I've owned one of these for about 10 months now and haven't used it past the first day because the results were all over the place. This is disappointing as I love the ALK/PO4 checkers. When testing I very carefully followed all instruction to the letter, used an insulin syringe for accurate fluid measurements, lab grade DI water (from a lab not my unit) and this yielded totally erratic results. JUST NOW I'm watching a 7 month old Hanna video and notice that the plunger on the reagent syringe was only being pushed down to the first mark before drawing NOT ALL THE WAY. I must have somehow missed this in the instructions. Anyone else have this issue and if so did it correct the problem?

Using this checker makes me feel like a little mad scientist and would love it if it actually worked!

Diesel · Feb 21, 2017

Using a CAL checker from Hanna you need to be always have 0.0 TDS in order to test, and I mean 0.000000 not 0.000001.
They aren't trust wordy in our hobby many ppl tried it but most of them dropped them and went back to the color chart.
Redsea and salifert are great for CAL

hybridazn · Feb 21, 2017

Diesel said:
Using a CAL checker from Hanna you need to be always have 0.0 TDS in order to test, and I mean 0.000000 not 0.000001.
They aren't trust wordy in our hobby many ppl tried it but most of them dropped them and went back to the color chart.
Redsea and salifert are great for CAL

Agreed, these have too many variables that can screw up the results. I would use red sea pro or salifert to test cal.

125mph · Feb 21, 2017

I just ditched my Hanna CAL checker as well. Every test was irratic.. But I don't have lab grade RODI water so I thought maybe it was that issue.

I just got a red sea calcium test and that works great.

jd371 · Feb 22, 2017

I have all three Po4, Alk, and Ca. When I first got the Ca I would check the readings against other kits and while the others would be close to one another the Hanna Ca would be all over the place. Tested with it a few times but always got the same results, so now it sits in the cabinet. I find it quicker to test Ca with Salifert as opposed to Hanna anyway.

Centerline · Feb 22, 2017

Diesel said:
Using a CAL checker from Hanna you need to be always have 0.0 TDS in order to test, and I mean 0.000000 not 0.000001.
They aren't trust wordy in our hobby many ppl tried it but most of them dropped them and went back to the color chart.
Redsea and salifert are great for CAL

Certainly a LOT faster! I use both of them now. I assume the lab grade stuff I bought was 0 TDS but maybe not. I tested last night with the plunger at the first indicator and got a wacky 360 measurement. RedSea put calcium at 475 and Salifert at 460.

Centerline · Feb 22, 2017

125mph said:
I just ditched my Hanna CAL checker as well. Every test was irratic.. But I don't have lab grade RODI water so I thought maybe it was that issue.

I just got a red sea calcium test and that works great.

Doesn't work for me and I did score the lab grade water.

Diesel · Feb 22, 2017

Centerline said:
Certainly a LOT faster! I use both of them now. I assume the lab grade stuff I bought was 0 TDS but maybe not. I tested last night with the plunger at the first indicator and got a wacky 360 measurement. RedSea put calcium at 475 and Salifert at 460.

So what does this tell you?

SPR1968 · Feb 22, 2017

Hi always used/use Red Sea and thought I might go digital so I ordered the Hanna Phosphate and alkalinity and a few days later the Calcium

The phosphate and Alk are fine and I tested against Red Sea (which are also good) and they were spot on.

However as soon as I opened the box of the calcium Hanna it was shut back tight and off back to the shop! The Red Sea is easy in any case so that's what I'm still using.

Centerline · Feb 22, 2017

Diesel said:
So what does this tell you?

Sub optimal tool for the specific job

Hanna Instruments · Feb 28, 2017

We apologize for any inaccurate readings you may have experienced. Our HI758 Calcium Checker uses a 100 to 1 dilution to analyze calcium. It is important to make sure you are using the new HI731339P volumetric pipette to administer saltwater sample to the cuvette. Any increased or decreased sample size will result in inaccurate readings.

http://hannainst.com/graduated-pipette-100-l-hi731339p.html

In addition, it is best to use a lab grade reverse osmosis/deionized water with near zero total dissolved solids when zeroing the Checker at C1 phase. Calcium can be found in many freshwater sources and any amount present in the original freshwater used can lead to inaccurate readings.

Also visit our blog to make sure you are following our 8 checker best practices such as indexing the cuvette in the same position every time, removing any air bubbles, finger prints or smudges and using separate pipettes/syringes for freshwater and saltwater.

http://blog.hannainst.com/checker-best-practices

You can also purchase a calibration kit for your Calcium Checker to make sure the device is not producing readings outside of our standards. The HI758 Calcium Checker does have an accuracy rating of ±6% of reading so there is some expected variations even if all best practices are followed.

http://hannainst.com/hi758-11-marine-calcium-checker-calibration-set.html

MaddyP · Feb 28, 2017

Hanna Instruments said:
You can also purchase a calibration kit for your Calcium Checker to make sure the device is not producing readings outside of our standards. The HI758 Calcium Checker does have an accuracy rating of ±6% of reading so there is some expected variations even if all best practices are followed.

In my opinion, this is the biggest issue with the Hanna Calcium checker. A ±6% reading at 420 ppm means the checker will read anywhere from 395 ppm to 445 ppm.

125mph · Feb 28, 2017

I used the new HI731339P volumetric pipette but the results were so inconsistent. It would show 560 on one test and then 390 on the next test. My RODI water is zero TDS but I thought maybe it wasn't lab grade so thats why it failed. Oh well, I returned the kit.

I wasted about 10 tests trying to get some consistency.. I even tested brand new Red Sea Salt mixed water, which is suppose to be 450ppm cal but it came out at over 500... The new test kit I got from Red Sea gets it dead on at 450ppm.. easy to use.

Hanna Instruments · Mar 6, 2017

We apologize for these inconsistent results you are experiencing. Make sure to follow the guidelines outlined in our video, which also help explain how to properly use the new pipette.

https://hannainst.wistia.com/medias/vjo7pa0pxk

In addition, when using a TDS meter to check the clarity of your RODI unit, its also best to make sure the unit has temperature compensation. Using a TDS meter without a temperature compensation can lead to inaccurate results. This is because as temperature increases/decreases it affects the mobility of ions and thus alters the TDS reading. Having a TDS meter with temperature compensation greatly affects the accuracy of the reading.

New Waterproof TDS Meter
http://hannainst.com/hi98301-dist-1...sc=42494650.7.1488807826824&__hsfp=2550584062

If you have any questions, comments or concerns about our products, you can always contact [email protected] or call 877-My-Hanna

Justin Swinney · Jul 26, 2017

I had some inconsistencies in results that I found checking against my Red Sea and API calcium tests. I found that my hanna checked was 100 higher than both. Last night when I do my nightly ca and alk test I tried something different. I rinsed the cuvette thoroughly 2 to 3 times with rodi water before using and my results of the three test kits were all within 10ppm. So don't rinse the cuvette with tap water. Tried this theory again today. Same results. My residual tap water in the cuvette was causing a high reading

Hanna Instruments · Jul 27, 2017

Justin Swinney said:
I had some inconsistencies in results that I found checking against my Red Sea and API calcium tests. I found that my hanna checked was 100 higher than both. Last night when I do my nightly ca and alk test I tried something different. I rinsed the cuvette thoroughly 2 to 3 times with rodi water before using and my results of the three test kits were all within 10ppm. So don't rinse the cuvette with tap water. Tried this theory again today. Same results. My residual tap water in the cuvette was causing a high reading

That will absolutely cause inaccurate readings. Since you are only using 0.1ml of saltwater sample, even trace amounts of tap water can cause false high readings due to naturally occurring calcium. Calcium is one of the predominate elements that make up water hardness in tap water and the Calcium Checker needs high quality deionized water to function correctly.

Centerline · Jul 27, 2017

Hanna Instruments said:
That will absolutely cause inaccurate readings. Since you are only using 0.1ml of saltwater sample, even trace amounts of tap water can cause false high readings due to naturally occurring calcium. Calcium is one of the predominate elements that make up water hardness in tap water and the Calcium Checker needs high quality deionized water to function correctly.

Interesting. I typically clean the culverts in tap water and then dry them with a twisted up paper towel. I wonder if enough residue is left in the culvers to cause a problem. Would be awesome if that's the case because its the only Hanna product I have ever been disappointed in.

ebushrow · Jul 27, 2017

you could always soak them in vinegar awhile and see if he readings are closer once they are "clean"

Hanna Instruments · Jul 27, 2017

Centerline said:
Interesting. I typically clean the culverts in tap water and then dry them with a twisted up paper towel. I wonder if enough residue is left in the culvers to cause a problem. Would be awesome if that's the case because its the only Hanna product I have ever been disappointed in.

It could be, we recommend never using tap water to clean any of your cuvettes, only DI water. This is standard practice for any laboratory equipment as the chemical makeup of your tap water can lead to introduction of potential contaminants for many tests. It is especially important for the calcium Checker that the water used at C1 phase is high quality Deionized Water, not distilled, with all ionic particles removed. Any measurable TDS (conductivity) can lead to false high readings since the Checker uses such a large dilution to measure calcium. Make sure any material that enters the cuvettes are clean and free of unwanted particles. Also make sure you are using a calibrated TDS meter if you are using home RODI water for your freshwater source. Many RODI systems for the reef market use inline monitors that are not calibrated, do not have temperature compensation and do not take into account that water from your reservoir can increase in TDS over time.

Hanna Instruments · Jul 27, 2017

ebushrow said:
you could always soak them in vinegar awhile and see if he readings are closer once they are "clean"

We sell cuvette cleaning solution that is anti static to prevent particles from sticking to the glass and removes any film that might build up over time

http://hannainst.com/hi93703-50-cuvette-cleaning-solution-230-ml.html

Water that is perfect for the HI758
http://hannainst.com/distilled-water-3-75-l.html

This is a great TDS meter to use for your RODI system, it is designed for low conductivity water.
http://hannainst.com/hi98308-pure-water-tester.html