So I got a new Hanna CA Checker...

[RussC]

When Hanna came out with the new CA checker, I thought I'd give it a shot. I love the ease and simplicity of the Hanna Checkers. And this one is no different. Relatively simple once you get the process. But my readings are consistently high compared to my Red Sea test. Anyone experiencing this?

For example...my most recent test with the Hanna checker was 438. But with the Red Sea it was 400. The day after I did a water change the Hanna registered 459. But the day after water changes the Red Sea registers around 430. There's a consistent average in the difference, but still, I think the Hanna is on the high side. I'm more likely to believe the Red Sea results than the Hanna results.

I don't dose CA at the moment. Not really been necessary. But its next on my list. Just got my ALK dose dialed in. So now I'm focused on CA.

 

[mcgyvr]

Hanna Color Checker states a precision as follows (I'm assuming its really accuracy is what they meant)..
Precision: ±6% of reading
Red sea defines accuracy -/+ 5ppm

Given those numbers both results seem to be "close enough" for test kits like that and between manufacturers..

 

[RussC]

Although the Hanna checker is higher than the Red Sea test, the changes in CA have been consistent in both tests. It would be nice to be accurate on the Hanna. I do like those tests. But it could be something as simple is CA in my RODI water throwing off the Hanna. If that's the case, oh well. I'll just have to roll with it.

 

[RussC]

How's the baby, Mac?

 

[outssider]

when testing with red sea are you ending when the sample turns blue, if so, this would explain the lower reading. You must keep swirling the vial for at least another 20 seconds or so. If the sample is still blue, you've reached the end point. It takes two or three more drops of reagent for the sample to stay blue without reverting back to some shade of purple /blueish color...… when it stays blue, this is the endpoint.

 

[RioReefr]

I use the Hanna Checker for Calcium. The problem I have with it is the literally 1-mL sample size. I have done consecutive tests back-to-back with the same water sample and gotten a +/- 30 difference. I use medicallly-sealed injectibale water in the test as well.
My eyesight is near perfect, but I use reading glasses to make sure everything measures to the level-line and use a tiny little syringe needle to get every little purple speck out of the reagent packets. All the vials are washed with vinegar, rinsed in RO/DI water and then thoroughly dried.
But, bottom-line with the super tiny amount of water there is just too much room for error (for a few drops of aquarium water used).

My advice is along as you getting something close to your "expected" result (i.e. 450 or whatever), then that is the best you can hope for. If you measure something like 420 and you think are going to "add so much X" of "this Z" to reach 430, then forget it !! To be perfectly honest, I bet the device has a +/- of 50 (or even more).

Hanna's Alkalinity is great, easy and accurate. But, the Calcium is much to be desired. Personally, I think you are better off with Red Sea.

 

[mcgyvr]

How's the baby, Mac?

Doing fantastic thanks for asking...Just hit 5 months old and is almost sleeping through the night.
Started him on some solid foods (bananas/pears/apples puree that we made fresh and put into pouches) and he is starting to roll over/sit up..
The grandparents (my parents) and my sister/her kids were all here this week to visit him so I had a full house all week..
My wifes sister/dad come in another 2 weeks...

Looks like I'll burn through all my vacation with everyone coming for visits so no beach vacation for us this year.. Maybe Christmas time cruise or something..

 

[RussC]

when testing with red sea are you ending when the sample turns blue, if so, this would explain the lower reading. You must keep swirling the vial for at least another 20 seconds or so. If the sample is still blue, you've reached the end point. It takes two or three more drops of reagent for the sample to stay blue without reverting back to some shade of purple /blueish color..."¦ when it stays blue, this is the endpoint.

You bring up a good point. When using the Red Sea, I give it a good 10 seconds once I see blue before I settle on that reading. If it starts to change, I give it another drop and wait another 10. I haven't given it 20 seconds as you recommended. But I could certainly try.

 

[mcgyvr]

You bring up a good point. When using the Red Sea, I give it a good 10 seconds once I see blue before I settle on that reading. If it starts to change, I give it another drop and wait another 10. I haven't given it 20 seconds as you recommended. But I could certainly try.

Yes not only does the testing device itself have some inaccuracy so do we as humans with a process like titration/color identification..

 

[NO3]

I don't care if my Calc is 420ppm +/- 30pm.

I think the problem is some people all want to spend $25 on a 50test kit and expect it to scientifically test within +/- 0.5% of the true exact number.

I know going in I'm not going to get an exact number but a range of:
* my calc is really low in the 350 range
* my calc is about right in the 420 range
* my calc is high in the 500 range

All tests imo are just "range finders"

Past that it would take me setting up a C.S.I. Lab in my basement

 

[Hastened]

Who cares if your Calc is 420ppm +/- 20

I think the op cares that's why he started the thread. Haha, lighten up bro.

Sent from my ONEPLUS A5010 using Tapatalk

 

[RussC]

Yea, just getting a feel to see if others might be seeing similar results when comparing tests. You are right. It’s really just a range.

Something I thought might be interesting is to check my RODI calcium. I guess the test will register it. Who knows. If I get to feeling froggy, I may give it a go.

 

[Joe0813]

My Hanna calcium checker is a pile of crap. It's constantly different numbers and constantly reading way off.. calcium was 430 with two different test kits and the Hanna was 552. Same with the Hanna ALK tester. Junk

 

[d2mini]

Hanna Alk is tester is the bomb. VERY consistent to the .1 for me.

 

[Joe0813]

Hanna Alk is tester is the bomb. VERY consistent to the .1 for me.

My alk tester almost nuked my tank. Would read 7.7-8.2 and I'd bump my dosing up. Come to find out, my alk was all the way up to 15

 

[homer1475]

My alk tester almost nuked my tank. Would read 7.7-8.2 and I'd bump my dosing up. Come to find out, my alk was all the way up to 15

I would dare to say user error. My Hanna ALK meter is within .1 of salifert or redsea kits(yes i have all 3, if one is off and I can cross reference with the other kits).



You do realize your supposed to use the same cuvette for both the zeroing of the meter(first step), and the color comparison? Changes in the glass can affect how the meter reads. No 2 cuvettes are the same.

 

[Joe0813]

Used the same glass and everything .

 

[Joe0813]

I'm not the first one to have issues with them, I've seen numerous posts with issues with the Hanna checkers

 

[d2mini]

Must have been something wrong with your unit or the reagent. Hey, it happens. No product is 100%.
But that's the first time I've heard anything bad about the Alk checker.

 

[2_zoa]

So, as mentioned by another. I wonder about giving the red sea test enough time. I know that in the beginning of using Red Sea tests. When I thought I was done I went ahead and waited the extra time only to see I needed to add another drop or two.

I also wonder about the water the sample is cut with. Unsure water will skew the result.

On top of those, I wonder about the testing location. After sitting in on one of Tullio's presentations on lighting. Then spending another 30 mins one on one with him. I totally forgot to ask this question. What type of lighting (temperature/color) is best, when testing or using a titration test? I've never seen this posted or written about. I've never seen anyone care. Yet, in my own pseudo tests. I can take a end test result from one rooms lighting and background color to another's......and get different test results. Titration seems to be very easily swayed based on surrounding conditions.