New Hanna marine checkers: magnesium and ammonia

[AJsReef]

Saw this on a FB page recently as well Cellar Marine shows the pre-order for April, shocked if it has flown under the radar this close to the release data. Judging by the instructions it seems much closer to the dKH checker than calcium which is a huge win!

 

[NigzWigz]

Maybe I was the only one who was left in the dark, but some German sites show:

• HI783 Hanna Marine Magnesium Checker
• HI784 Hanna Marine Ammonia Checker

I'm so glad I won't have to do any more titration tests. Anyone else is very keen to try out the new magnesium checker?

The Magnesium one is scheduled for release on April 15 in Germany.
Range: 1000-1800 ppm / Resolution: 5 ppm / Accuracy: ±5% of the reading at 25°C
By google-translating the manual on Hanna's German site, it seems pretty easy to use.

• Prepare your "blank" with 4 ml of reagent A, plus 5 ml of unreacted sample
• Put the "blank" into checker, press the button, wait for C2
• Get the "blank" out of the checker, add 1 ml reagent B. Invert 5 times.
• Put the reacted sample back into the checker. Press button once. (no waiting time), the display shows the result.

The ammonia one looks a tad more complex:
Range: 0-2.5 ppm / Resolution: 0.01 ppm / Accuracy: ±5% of the reading at 25°C

• Prepare your "blank" by adding 14 drops of reagent A and one sachet of reagent B to 10 ml of unreacted sample.
• Shake the "blank" gently for 30-45 seconds, and let the "blank" stand for 30 seconds to eliminate bubbles.
• Put the "blank" into checker, press the button, wait for C2.
• Get the "blank" out of the checker, add 12 drops of reagent C. Invert 5 times.
• Put the reacted sample back into the checker. Press and HOLD the button. After a 15 minutes wait, the display shows the result.

The steps of the ammonia checker remind me a lot of the Red Sea ammonia test. Same reagents: two droppers, one powder. Same wait time: 15 mins.

View attachment 2576609

Just now ordered the HI783 directly through HANNA via phone (there's a page error when trying online at the moment) for the US. According to the sales rep, they are on back order till May 9th. All orders places now will be fulfilled once they come in. Total price for the checker and shipping came out just under $80. You wanna save a little money, I guess you one can wait to pick one up at their LFS. There's a finite amount, so best of luck!

 

[CoralB]

Based off their alk(reagent) and calc checkers i dont trust them enough to hand over any more of my money without seeing a lot of reviews.

What’s the issue with the alk checker ? I thought it was more reliable ?? Sorry for the lateness of this question .

 

[Gtinnel]

What’s the issue with the alk checker ? I thought it was more reliable ?? Sorry for the lateness of this question .

Many people get different readings for alk when using different bottles of reagent.

 

[wotis11]

Well the calcium one is inherently flawed because of the miniscule amount of the sample water, no? This one uses a much larger amount of sample, and no RO/DI with potential traces of mag / calcium.

Technically you’re not supposed to use RO water with the calcium checker. You’re supposed to use Hanna’s deionized water with it. I always use their water and I have never had a problem with it

 

[Randy Holmes-Farley]

Technically you’re not supposed to use RO water with the calcium checker. You’re supposed to use Hanna’s deionized water with it. I always use their water and I have never had a problem with it

Which to me is a design flaw.

It would be like a Ford car requiring special Ford water in the radiator (IMO).

 

[Gtinnel]

Which to me is a design flaw.

It would be like a Ford car requiring special Ford water in the radiator (IMO).

Sadly the car coolant analogy does happen in the automotive world. I’ve had a few cars that said to only use their brand coolant.

 

[Muffin87]

Technically you’re not supposed to use RO water with the calcium checker. You’re supposed to use Hanna’s deionized water with it. I always use their water and I have never had a problem with it

I don't think this is a fair characterisation. I don't believe Hanna has ever said you're supposed to use the deionised water they sell.

Because with the calcium checker the sample is so small, you are supposed to use deionised water that you know not to contain even the smallest trace of calcium. I won't call such water "lab grade", because that really doesn't mean much.
Hanna sells such water, but you can produce it yourself, or buy it in different places. For example, a user has been in contact with Hanna to discuss differences in test results using deionised water from CVS, versus that from Walmart.

Also, it seems a number of people may be using RODI for the testing procedure but are using tap water to clean the cuvettes/pipette they run the test with. Using tap water is known to skew the results:

After each test, the volumetric pipette tip and the glass cuvette should be rinsed in deionised water and never in tap water. As I mentioned before, the main reason previous users had inconsistent results while using Hanna Calcium Checker was because of the use of tapwater to clean the equipment. You saw in my description that the water sample is really small in volume and with most water running from our home taps being high in Calcium content, even a slight residue may skew the test results (source).

 

[wotis11]

I don't think this is a fair characterisation. I don't believe Hanna has ever said you're supposed to use the deionised water they sell.

Because with the calcium checker the sample is so small, you are supposed to use deionised water that you know not to contain even the smallest trace of calcium. I won't call such water "lab grade", because that really doesn't mean much.
Hanna sells such water, but you can produce it yourself, or buy it in different places. For example, a user has been in contact with Hanna to discuss differences in test results using deionised water from CVS, versus that from Walmart.

Also, it seems a number of people may be using RODI for the testing procedure but are using tap water to clean the cuvettes/pipette they run the test with. Using tap water is known to skew the results:

I stand corrected. I just double checked the instructions on the Hanna calcium checker and it does say use deionized water, not their water. But I use their water and have never had a problem. It must just be because their water doesn’t contain any traces of calcium in it. But you are correct that you can use any deionized or RO water that doesn’t have any traces of calcium in it

 

[Randy Holmes-Farley]

I understand that one can use any distilled water. It’s still a bad design.

 

[piranhaman00]

I understand that one can use any distilled water. It’s still a bad design.

It’s a bad design to need ultra pure water for a chemical analysis?

 

[Randy Holmes-Farley]

It’s a bad design to need ultra pure water for a chemical analysis?

Certainly.

A test should not be designed where 1 ppm calcium in the blank causes more than 1 ppm calcium error in the final value.

That is accomplished by using the same sample size for the blank and the tank water. That is how most methods would work.


But NOOOOOOO. Hanna designs it this way:

"The HI758U Marine Calcium Checker HC® uses a 100 to 1 dilution for analysis and thus requires deionized or distilled water absent of calcium to function correctly. "

It's a standard idea that blanks should be as similar to the sample as possible, not where one is diluted and the other is not:

The Vital Role of Blanks in Sample Preparation

Blanks are important in the pursuits of quality control and robust quantitative analytical methods, but many analysts don’t fully understand their value, or how to use them correctly.

www.chromatographyonline.com

"Types of Blanks
Blank samples are collected, stored, treated, and analyzed in a manner as close to that for authentic samples as possible to account for contaminants and other potential interferents or potential sample degradation. "

 

[moorjames]

I am with you! Takes forever to test. I don’t know how many times I lost track on how many single drops I put in when mixing in between each drop. But I do love the accuracy!

I thought I was the only moron who loses count after every...single...drop...

 

[Christoporia]

I hope the magnesium one works better than their calcium checker.

So first time using this magnesium checker, it flashed 1800, which means my sample is over range. Manual says to dilute the sample and test again, but no further instructions on how. Considering there are 2 reagents, what exactly should I dilute? My thought would be to dilute the second reagent by half to get a number and multiply by 2 for results. Sound idea or flawed thinking?

 

[Muffin87]

So first time using this magnesium checker, it flashed 1800, which means my sample is over range. Manual says to dilute the sample and test again, but no further instructions on how. Considering there are 2 reagents, what exactly should I dilute? My thought would be to dilute the second reagent by half to get a number and multiply by 2 for results. Sound idea or flawed thinking?

I believe they mean you should dilute the sample water with either rodi or seawater with a known magnesium content, such as a reference solution

 

[Randy Holmes-Farley]

As muffin suggests, the dilution is of the tank water sample. If Hanna says it is Ok to dilute, then mix 1 part RO/DI with 1 part tank water, and test the normal volume of that fluid.

Then multiply the value by 2.

I'm suspicious since levels over 1800 ppm are pretty unusual unless you are trying to get very high.

 

[Christoporia]

As muffin suggests, the dilution is of the tank water sample. If Hanna says it is Ok to dilute, then mix 1 part RO/DI with 1 part tank water, and test the normal volume of that fluid.

Then multiply the value by 2.

I'm suspicious since levels over 1800 ppm are pretty unusual unless you are trying to get very high.

I diluted by 50% with RO and tested again, got 1000 flashing, indicating too low range. I tested again and diluted by .33% and got a reading of 1100ppm. Did the math and came up with 1650 for my result. Not sure why the first test blinked 1800 (over range) if it is sitting at 1650. Gonna do a full strength test again tomorrow.

 

[Woodyman]

I diluted by 50% with RO and tested again, got 1000 flashing, indicating too low range. I tested again and diluted by .33% and got a reading of 1100ppm. Did the math and came up with 1650 for my result. Not sure why the first test blinked 1800 (over range) if it is sitting at 1650. Gonna do a full strength test again tomorrow.

Just out of curiosity did you also test using your previous titration method from prior to buying the Hanna?

I'm curious about your historical Mg values, and a side by side of how you previously tested and the new checker.

 

[Christoporia]

Just out of curiosity did you also test using your previous titration method from prior to buying the Hanna?

I'm curious about your historical Mg values, and a side by side of how you previously tested and the new checker.

Normally testing with Salifert and it has been off the scale on that test also. It takes the entire syringe of the last reagent to even slightly change color.

 

[amazongb]

Salifert is way easier for mag and calcium. My Hanna ALK has been unreliable lately due to reagent issues, so probably switching that the Salifert as well. The Salifert tests are so simple and fast.