Hanna Alk Checker inaccurate?

[brianbo493]

I bought a Hanna Alk checker from a lfs and been using it for about a month and was getting readings of 9.0 9.2. I was thinking thats great, I decided to get my water tested at a lfs and they said my alk was 7.2 I didn't think that could be right so when I got home I rechecked my alk and it was 9.1. So I went to a different lfs to compare the test and they also said my alk was 7. So now Im thinking its my checker. Has anyone else had an issue with theirs. Also I only use RODI water to clean the vials, and make sure there clean and clear before putting them in the checker

 

[rkpetersen]

I personally would probably trust my Hanna checker more than my LFSes.
The Alk Checker can vary from batch to batch, it's true, but in my experience, generally less than 0.5 dKH.
I have heard of up to 1 dKH difference between two batches, but I haven't seen that personally, and I've gone through many dozens of bottles.
My current Alk Checker reagent runs about 0.3 dKH lower than the Trident. I consider this difference to be insignificant.
One thing you can do is buy a bottle of alk standard, and run that in your checker. Neptune Trident Calibration Solution, FaunaMarin Multi-Reference, and GHL Alk/dKH Reference would all answer your question.

 

[Philly Reefer]

Do you have a different test kit that you can try?
What salt are you using? And the salinity?

 

[brianbo493]

I do not have another test, the 2 shops I went to used an api and a Sera test. Im using HW marinemix reefer and its at 1.026

 

[Philly Reefer]

What is marine mix description when you mixed it at 35ppt?
Not sure about sera test, but isnt the api based on drops? Totally not accurate at all...
You probably want to get another test kit or the kh solution like rkpetersen said.
But unfortunately, cant calibrate the hanna. But since you just bought it, you can call hanna and ask for replacement

 

[brianbo493]

Ya I know there not very accurate, but to have 2 different test come back with readings in the 7s got my thinking, it says 9.0dkh

 

[Philly Reefer]

Ya I know there not very accurate, but to have 2 different test come back with readings in the 7s got my thinking, it says 9.0dkh

Any friends that can come by and test it with their test kit?

 

[brianbo493]

I gave Hanna a call and there sending me a new bottle of reagent to try out

 

[rmurken]

I honestly wouldn’t worry too much. Variation between different alk test brands seems to be more the norm than the exception. As long as your tank looks good and your Hanna results are internally consistent, I’d just go with it.

I had the Red Sea pro and Hanna Alk together while I switched from RS to Hanna, and noticed a similar issue. They tracked each other, but stayed a good dKh apart.

Healthy tanks can exist in a pretty wide band of alkalinities as long as you pick a target level and keep it consistent. Who cares if your test calls it 8 or 9 or 10.

 

[92Miata]

My red sea test reads 7.6 while my Hanna reads 8.5.

The fact that Hanna's reference solution is 5dkH is a huge fail.

 

[Randy Holmes-Farley Verified Community Expert]

Another reason to use a DIY that you know works.

 

[Marc2952]

I always test a new batch against the old one and calculate the difference, you will nevee have a problem then. Fishofhex did a video on it.

 

[LeftyReefer]

This is not the thread I was hoping to read a day after ordering a new Hanna Alk checker. ugh.

 

[Philly Reefer]

This is not the thread I was hoping to read a day after ordering a new Hanna Alk checker. ugh.

I think for most ppl the hanna checker has been accurate

 

[Marc2952]

This is not the thread I was hoping to read a day after ordering a new Hanna Alk checker. ugh.

Hannan alk checker was one of the best purchases ive made lol

 

[Randy Holmes-Farley Verified Community Expert]

I think for most ppl the hanna checker has been accurate

Most are only hoping it is accurate as few folks actually have checked the accuracy. It is not easy to do.

 

[Philly Reefer]

Most are only hoping it is accurate as few folks actually have checked the accuracy. It is not easy to do.

I guess I should rephrase that most people have good experience with the hanna alk due to the simple steps to test and easy to read result. (I always doubt if it pink enough on other test)

for accuracy, I checked it with testing newly mixed saltwater. I.E. Tropic marin pro @7dKh on 35ppt. Not really reliable but as a hobby test kit. It will do.

 

[Marc2952]

Most are only hoping it is accurate as few folks actually have checked the accuracy. It is not easy to do.

Woulsnt it be accurate enough if you just test the new batch against the old batch and calculate the difference? Ive never had issues that way.

 

[GlassMunky]

I do not have another test, the 2 shops I went to used an api and a Sera test. Im using HW marinemix reefer and its at 1.026

There’s your issue right there.... they are using shoddy tests while yours is much more accurate

 

[Randy Holmes-Farley Verified Community Expert]

Woulsnt it be accurate enough if you just test the new batch against the old batch and calculate the difference? Ive never had issues that way.

Batch of what? Reagents for the kit?

That's no test of accuracy, just reproducibility of the reagents.