Hanna vs salifert

[VanDalsenReef]

So I've been using hanna and salifert alkalinity tests kits to go off each other to make sure they're close. Recently my hanna has been giving me higher numbers. I have changed reagents and it's still high. My tank used go run around 7 and now it sits around 8 (give or take 0.2) with my hanna. My salifert says 7 give or take (0.3). I thought it was strange so I mixed fresh saltwater and thought if it's close to what the salt states then maybe my hanna or salifert is off and poof at 35ppt the alk was 7 on my salifert and 7.9 on hanna. Should I trust my hanna more or my salifert test? My hanna has been very accurate and now it's off? Two different reagents and they're the same with the checker but salifert is closer to what the salt states (tropic marin pro reef)

 

[VanDalsenReef]

Even more "strange" is that these reagents came from Amazon instead of my usual fish places. Coincidence?

 

[VanDalsenReef]

Anyone know of this or what I should do?

 

[Muffin87]

You should get a reference solution and test your test kits. Id recommend the ati reference solution purely because it's huge, 1000 ml, in comparison to most reference solution.

Hanna also offers calibration check sets for each one of their checkers, you can google the code of your checker (e.g. HI755) and add -11 to find its calibration check set.
The HI755-11 is the calibration check set for the hanna alkalinity checker, ppm version.

 

[xabo]

May be worth a read: https://www.reef2reef.com/threads/i...-for-hanna-marine-alkalinity-checkers.893762/

 

[Randy Holmes-Farley]

You should get a reference solution and test your test kits. Id recommend the ati reference solution purely because it's huge, 1000 ml, in comparison to most reference solution.

Hanna also offers calibration check sets for each one of their checkers, you can google the code of your checker (e.g. HI755) and add -11 to find its calibration check set.
The HI755-11 is the calibration check set for the hanna alkalinity checker, ppm version.

I'm not a fan of the Hanna solutions as all they do is check the electronics and that may give reefers a false sense of accuracy when other issues are more often the problem (e.g., reagents getting old).

A true standard is better, IMO.

 

[Randy Holmes-Farley]

So I've been using hanna and salifert alkalinity tests kits to go off each other to make sure they're close. Recently my hanna has been giving me higher numbers. I have changed reagents and it's still high. My tank used go run around 7 and now it sits around 8 (give or take 0.2) with my hanna. My salifert says 7 give or take (0.3). I thought it was strange so I mixed fresh saltwater and thought if it's close to what the salt states then maybe my hanna or salifert is off and poof at 35ppt the alk was 7 on my salifert and 7.9 on hanna. Should I trust my hanna more or my salifert test? My hanna has been very accurate and now it's off? Two different reagents and they're the same with the checker but salifert is closer to what the salt states (tropic marin pro reef)

I do not know which, if either, is more accurate, but it seems that on average, folks get slightly higher readings with the Salifert alk kit compared to the Hanna. You are getting the opposite, so nothing is clear about which is better. lol'

You can red more here on what the color should look like at the Salifert endpoint:

Alkalinity titration endpoint pH & Salifert endpoint color

TL;DR: The endpoint pH is 4.41, and the endpoint color is that "lavender" color I've been telling people about. Over the years, there have been many threads on R2R and other forums debating a couple of basic details relevant to testing for alkalinity in reef aquaria. One of the most...

www.reef2reef.com

 

[Goodersgold]

I have a similar issue with my Hanna Phosphate checker. I have relatively new system that I monitoring closely before adding coral. I brought a brand new Hanna Checker, my first reading was 2.5 which was alarming, PH 8.1, Alk 8.2, Cal 360, Sal 0.126. I added some RowaPhos and tested again (10 days later) Hanna still reading 2.49, yet testing with Salifert, reading was closer to 0.3, should I send the Hanna back to be checked, seems the only way forward?

 

[Dan_P]

So I've been using hanna and salifert alkalinity tests kits to go off each other to make sure they're close. Recently my hanna has been giving me higher numbers. I have changed reagents and it's still high. My tank used go run around 7 and now it sits around 8 (give or take 0.2) with my hanna. My salifert says 7 give or take (0.3). I thought it was strange so I mixed fresh saltwater and thought if it's close to what the salt states then maybe my hanna or salifert is off and poof at 35ppt the alk was 7 on my salifert and 7.9 on hanna. Should I trust my hanna more or my salifert test? My hanna has been very accurate and now it's off? Two different reagents and they're the same with the checker but salifert is closer to what the salt states (tropic marin pro reef)

There is no point in comparing two imperfect things to determine which is more imperfect. The only way to answer your question is by measuring a known alkalinity, a standard.