Hanna Alkalinity Checker- Accuracy?

[mphammer]

I am curious to hear what people think about the accuracy of their Hanna Alkalinity checkers. Or if you use something else and why.

Long story short, my alk was testing super low (5.6) in my latest tank setup so I have been dosing to raise. Then just to see, I tested my salt mix, which also came in at 5.6. Thought I had bad salt, bought new salt and it tested at 5.8....
Went to LFS, bought salifert test and my fresh salt mix tests at...11.2. And of course my tank, which I have been dosing like crazy, is at 13.7. Thanks Hanna. Valuable lesson, always test your tester

 

[york1]

I keep backup test for all of my hanna checkers. That way when I get an odd reading I can double check. My hanna alk checker has been pretty accurate and consistent Im glad you got that sorted out.

 

[ichthyoid]

+1
If something seems odd, it likely is. Or, at least deserves a 2nd opinion.

That said, Hannah checkers are very reliable. The review in the link below says it’s on the money compared to Salifert. They are also within 5% of analytical standards.

Possibly your technique?

Hanna Instruments Alkalinity Checker- a Definitive Review

Alkalinity. The only correct answer to the question: What’s the most important parameter to keep in check in order to grow SPS corals successfully? One can ar

reefs.com

 

[Trizzino]

I used to have issues with their reagents that was a bad batch but since then it’s been pretty solid. I ran into the same problem as you. Kept reading low so I upped dosing. Read low, tested new salt, low. Then I bought a salifert Kit and it proved it was a bad reagent.

I always test twice and if they are close and expected I’m good. If it strikes me as odd I test with my backup salifert.

 

[mphammer]

I used to have issues with their reagents that was a bad batch but since then it’s been pretty solid. I ran into the same problem as you. Kept reading low so I upped dosing. Read low, tested new salt, low. Then I bought a salifert Kit and it proved it was a bad reagent.

I always test twice and if they are close and expected I’m good. If it strikes me as odd I test with my backup salifert.

I am thinking it was the reagent. When I first opened the unit, there was a small puddle under the reagent bottle hinting it was never properly sealed. I am going to grab another bottle of reagent and test against salifert.

 

[mphammer]

+1
If something seems odd, it likely is. Or, at least deserves a 2nd opinion.

That said, Hannah checkers are very reliable. The review in the link below says it’s on the money compared to Salifert. They are also within 5% of analytical standards.

Possibly your technique?

Hanna Instruments Alkalinity Checker- a Definitive Review

Alkalinity. The only correct answer to the question: What’s the most important parameter to keep in check in order to grow SPS corals successfully? One can ar

reefs.com

Could definitely be, but the procedure is very similar to the phosphate and calcium Hanna checkers I use with great accuracy. I think the culprit here is the reagent I was using.

 

[bzb]

Almost guarantee it's the reagent. Try a fresh bottle and see what happens.

I have the Hanna but if I get an odd reading I'll test it against the Salifert and the super cheap (but only accurate at whole numbers) Tropic Marin. Generally they're all pretty close.