Product Review: Calcium and Phosphate Hanna Checkers

[NC2WA]

My name is Kirk and I am going to give a review of the Hanna Checkers for phosphate and calcium.
I will tell you how they work, what I like about it, and what I would like to change.

Hanna Checker Phosphate (PO4):

Included in the PO4 checker:
Checker
1 1.5v AAA battery
Powder reagents for 6 tests
2 test curvettes (vials)
Instruction manual

Note: All of the equipment fits nicely in a white box that is provided.

The steps to perform a PO4 test are:

1. Turn on meter, and then press button. “C1”, “Add” is displayed. Meter is ready
2. Fill curvette with 10ml of sample (tank) water. Place curvette in meter and close lid
3. Press button. “Add”, “C2” is displayed. Meter is calibrated (zeroed).
4. Remove curvette from meter and add reagent powder. Cap curvette and shake for 2 minutes. Place curvette back in meter and close lid
5. Press and hold button until 3:00 timer is displayed. After 3 minutes, the PO value is digitally displayed.

Note: The meter will automatically turn off after 10 seconds.

I love this checker as it is able to display values higher than 1.0 AND the value is digitally displayed. To test this accurarcy, I purchased one other popular Phosphate test kit: Elos


The PO4 results are noted in Table1:

	Elos**	Hanna Checker
09/30/11	1.0	2.00
10/15/11	1.0	1.68
10/22/11	1.0	1.75

Table 1- PO4 test results
**-Test kit not able to display higher than 1.0


Conclusion: Two thumbs up and is a must purchase to have.

This is a definitely worth the purchase as the meter is able to display a range from 0.00 to 2.50 ppm. No more trying to guess what shade of blue your vial is, as the value is digitally displayed. The steps to this meter were straight forward and easy to understand.

There is a higher Phosphate meter than can be purchased if you feel your PO4 level is higher than 2.50 ppm. A complete listing of available checkers see Global comments located at the bottom of this article.



Hanna Checker Calcium (Ca):

Included in the Ca checker:
1 1.5v AAA battery
1 checker (meter is used in instructions)
2 sample curvettes (vials)
Powder reagents (HI 7582, Reagent B) for 25 tests
1 bottle of liquid reagent A
1 dropper
2 x 1ml syringes with tips
Instruction Manual

This checker contains the most steps of any checker. The steps are the following:

1. Turn on meter by pressing button. “Add”, “C1” is displayed which means meter is ready.
2. Add 1 ml of Reagent A to curvette using syringe. Use dropper to fill to 10ml mark using deionized water. Invert 3-5 times to mix.
3. Place curvette in meter, close cap, and then press button. When “Add”, “C2” is displayed to meter is calibrated or zeroed.
4. Remove curvette from meter. Add 0.1 ml of sample (tank) water to curvette using the syringe
5. Add 1 packet of Reagent B to curvette, replace cap and shake briskly for 15 seconds. Allow bubbles to dissipate for 10 seconds before taking your
reading.
6. Place curvette back in meter, close lid, and then press button. The meter displays Ca level.

Note: The meter will automatically turn off after 10 seconds.

Due to the chemistry that is involved with this meter, this meter has the most steps. To me this is inconvenient, however the end result is a digital number that is accurate. To test this accurarcy, I purchased two other popular Calcium test kits: Elos and Salifert.
The results are noted in Table 1:

	Elos	Hanna Checker	Salifert
09/30/11	600	600	430
10/15/11	550	454	380
10/22/11	550	450	375

Table 1-Calcium test kit results


Conclusion: Hanna Checker unit was just as accurate as the Elos test kit. With the Hanna Checker you have an instant digital output of your calcium level. The range of the Hanna checker is 200 to 600 ppm.

The steps to this meter were complicated and sometimes hard to follow. If you need a quick check on Ca level, I will prolly use the Elos test kit as I am familiar with the steps. But for those that want an accurate digitally displayed number, the Hanna Checker is your tool of choice and one that I will use.

Global comments on both checkers

To get an accurate reading the following suggestions are giving by Hanna:

• Ensure outside of vial is clean and dry
• Ensure vial is free of any debris
• Ensure vial is free of thumbprints, oil, or dirt
• Ensure there are no bubbles in the vial as bubbles can cause a higher reading
• Do not leave sample vial stand to long after reagent is added as accuracy will be lost
• After reading is displayed, disregard sample from vial as glass may become permanently stained

The complete list of checkers that are available for saltwater use:

• HANNA HI 713 Checker HC - Phosphate Low Range
• HANNA HI 736 Checker HC - Ultra Low Range Phosphate (tests 0-200 ppb Phosphorous (as phosphate)
• HANNA HI 764 Checker HC - ULR Nitrite
• HANNA HI 755 Checker HC - Marine Alkalinity
• HANNA HI 758 Checker HC - Marine Calcium
• HANNA HI 717 Checker HC - High Range Phosphate

When the Magnesium and Ammonia checkers are available, I will be purchasing them. Overall, I am a fan of Hanna checkers as I like the precise number that is digitally displayed, no more guessing and trying to match up numbers to a color chart or counting drops and then doing math.

 

[Krish]

Nice job Kirk!!! Thanks for putting it together.

 

[returnofsid]

With either of these products, did you have a known standard to test? I ask due to the big difference, in the Calcium test kit, between Elos and Salifert, that you ended up with. How were you able to determine that the Elos test kit was accurate and that the Salifert test kit was that far off? You ended up with a Calcium result of 600 and a result of 430. My concern would be with the result of 600, unless you were testing a known standard, that was supposed to be 600. Otherwise, a calcium level of 600 would be pretty hard to get, without a huge overdose of calcium supplement.

 

[NC2WA]

Michael,

High Ca level was to be expected as I had been heavily dosing calcium and Mg for several days before the test. Mg level at the time of the test was 1450.

I cannot explain the low level from the Salifert test, however if there is anyone nearby that knows their Ca level, I would be more than happy to test it using my Hanna checker to see what the accuracy level is.

I agree that performing more test does increase the degree of accuracy, which in turn gives more relability

 

[Maxx]

How old were the test kits you were using as comparisons to the Hanna testers?

Nick

 

[mojoreef]

Kirk was the hanna checker blinking when it was reading 600?

Mike

 

[NC2WA]

Nick--The Salifert and Elos test kits were brand new with expiration dates of 2014

Mike-Yes, blinks for 10 sec the meter is turned off.

 

[returnofsid]

I just find it really difficult to understand how calcium, at a level of 600, would even stay dissolved. At "reef temperatures," calcium will typically precipitate at anything above 550. I mention temperatures only because temperature does effect saltwater's ability to "hold" calcium in solution.

It'd be really interesting to run these same tests, against a known standard. The problem is, finding that standard...lol. It seems, recently, a lot of synthetic salt mixes have been found to have calcium levels that are different than advertised. Maybe Boomer will chime in soon. Maybe he can give us directions on making a known standard for Calcium.

 

[NC2WA]

Agreed. Waiting for Boomer.. :-D

 

[Darthv247]

+1 to the checkers. i like the digital readout and no need to try and match up color charts. alkalinity is nice but yah the calcium one is just as difficult as normal tests aside from trying to match up color charts or count drops.

 

[NC2WA]

Darth,

Glad I wasn't the only one that thought the same thing for the calcium test. When I first perfomed the steps, I said to myself, "self, this is not any easier than a regualr test kit".

 

[Boomer]

Kirt

Conclusion: Hanna Checker unit was just as accurate as the Elos test kit. With the Hanna Checker you have an instant digital output of your calcium level. The range of the Hanna checker is 200 to 600 ppm.

Is meaningless unless all are checked against a std. There are LOTS of issues with these Hanna units being way off. The RC chem forum is filled with them from many of my posts and others they have had to mod units and give new instructions. Their PO4 is fine and has run the mill of countless tests against very expensive photometers like HACH and LaMotte. These others, i..e., Alk, Ca++ seem to fail all tests. I can not count the times Hanna has come to the RC Chem forum with "oops" you guys are right we we will try to fix it. Their Alk has been a mess. Just because it is digital DOES NOT mean it is correct or accurate. Getting that 600 ppm with that Hanna when that is its limit tells me something is very, very wrong. Where is it written the Sailfert is incorrect or the Elos is ??? What are the expiration dates of the kits, where was the second and third Hanna, Salifert and Elos for better verification. You can not take one of each and draw any conclusion what so ever. It all makes about as much sense as taking on refract and one swing-arm hydrometer and saying the refract MUST be correct, because it is a refract but we have proved that not to be the case many times and the refract is way off.



Nick
. At "reef temperatures," calcium will typically precipitate at anything above 550.

Not, so as it is a function of temp, Alk and pH. At "reef temperatures", with a pH of 8.1, Alk 2.5 meq / l you can go way over 600 ppm with out precip. At 8.2 pH , Alk 2.5 meq / l you will start to get precip Ca++ precip near 800 ppm.



DIY Ca++ std is not a easy task by a long shot but this will get you in the ball park.

1. Get some ACS Grade Calcium Chloride Dihydrate
2. Take 998.5 ml of RO/DI water
3. Add 1.5 grams of Calcium Chloride Dihydrate to that 998.5 ml of RO/DI

You will be close to 425 ppm but more likely somewhere between 400 -450 and more toward the 425 - 450. Reason is the water the Calcium Chloride Dihydrate my/will adsorb.




You are better off doing this


NexSens Calcium Standard Solution
http://www.fondriest.com/products/nexsens_sd0ca1-500.htm

 

[NC2WA]

Boomer,

I will see about creating a standard in a couple of days.

All the other test kits had an expiration date of 2014. I would think since I did 3 Ca test on different dates (see table in article) and the Hanna checker and Elos were about the same, one could assume that values from the meter were accurate. From what I'm reading in your reply, this is not the case.

I will agree this article is far from scienitific, but the point of the article was to give my findings and what I like and didnt like about them.

 

[Boomer]

Kirt

I would think since I did 3 Ca test on different dates

You need 3 meters, 3 Salifert and 3 Elos, you can not just use one of each, there is to much built error, i.e, that one meter or one kit may bad. You need to repeat the result using all 9 of them. Pretend you have another Hanna meter and it reads the same as the Salifert then what ?? However, with a std you can by-pass this.