Important findings according how to store open bottles of the reagent for Hanna Marine alkalinity checkers

[Reef.]

I have also found that when i get to the bottom of a bottle I start to see wired results. Good to know

It’s not clear if the last of the bottle is meant to be used, The bottle I believe has 30ml but the instructions say it’s good for 25 tests, so seems to suggest the last 5mls is not meant for tests, but Lasse’s results seems to over come any issues with using the full bottle.

 

[hotdrop]

It’s not clear if the last of the bottle is meant to be used, The bottle I believe has 30ml but the instructions say it’s good for 25 tests, so seems to suggest the last 5mls is not meant for tests, but Lasse’s results seems to over come any issues with using the full bottle.

I sometimes get funky results at the last 10 ml or so. It’s really thrown me for a loop. I think maybe the reagent evaporates or something because the bottle does not always have a great seal

 

[Reef.]

I sometimes get funky results at the last 10 ml or so. It’s really thrown me for a loop. I think maybe the reagent evaporates or something because the bottle does not always have a great seal

Definitely they have the extra fluid there for some reason, to add an extra 20% or so but to tell you not to use it seems strange.

 

[kenbennedy]

For what it’s worth, I ran 2 tests today back to back. First test was my open bottle of reagent, which I opened right before Xmas (12/19/2021 was my first recorded test). 2nd test was with a new reagent bottle, opened today. I used the same cuvette for both tests (rinsed in between), same colorimeter, and same syringe to fill 10mL of sample water.

”Old” reagent gave an 8.2 dkH reading
”New” reagent gave 8.4 dkH reading

Had I been more forward thinking, I would have taken a few more data points to better determine repeatability, but it is what it is at this point. I’ll just keep both bottles in the refrigerator going forward and use the older bottle first. I am not going to lose sleep over .2dkH accuracy, but now I am curious about the repeatability.

 

[gbroadbridge]

For what it’s worth, I ran 2 tests today back to back. First test was my open bottle of reagent, which I opened right before Xmas (12/19/2021 was my first recorded test). 2nd test was with a new reagent bottle, opened today. I used the same cuvette for both tests (rinsed in between), same colorimeter, and same syringe to fill 10mL of sample water.

”Old” reagent gave an 8.2 dkH reading
”New” reagent gave 8.4 dkH reading

Had I been more forward thinking, I would have taken a few more data points to better determine repeatability, but it is what it is at this point. I’ll just keep both bottles in the refrigerator going forward and use the older bottle first. I am not going to lose sleep over .2dkH accuracy, but now I am curious about the repeatability.

Keep in mind that two bottles from different batches opened at the same time, can differ by up to 0.4dkh in my experience.

Hanna checkers are convenient with the digital display, but are no more accurate than any other hobby grade test kit and are subject to the same variations.

 

[Aimforever]

Makes me wonder if similar deterioration is at play with the Neptune trident reagents, possibly contributing to some of the inconsistencies seen with testing.

 

[Lasse]

I´ll think that its important to stress that these findings is valid for me. When I start to have my reagent in the refrigerator the problem with a stable down going in the result disappear. It could be caused of the storage in lower temperature (what I think) but also that I all the time had have bad reagents and I of some reasons got good reagents after that (IMO rather unlikely - but still possible).

When people that have had the same problem as I have test my method and get the same or different result - we will be closer to the truth.

Whit this in mind - feedback is very important

Sincerely Lasse

 

[Reef.]

Keep in mind that two bottles from different batches opened at the same time, can differ by up to 0.4dkh in my experience.

Hanna checkers are convenient with the digital display, but are no more accurate than any other hobby grade test kit and are subject to the same variations.

I agree, especially with the alk, I find salifert and Aqua forest very accurate, I feel the only benefit with the Hanna for alk is ease of use, the Hanna po4 tho is in a class of its own as other test kits are next to impossible to read.

 

[GoVols]

There is a way to hinder the Hanna alk to show lesser and lesser dKH (or ppm for that matter) with age of open reagent bottle. I had the same story as many have reported here - my reading decrease from a new open bottle with time. Double check with another method show that there was not a real decrease - only that the reagent did not give the colour it should. Comparing with a fresh newly open bottle confirm the false readings of the old reagent. I did a test with shaking the bottle every time I use it - not better result. After this I start to store all open bottles in my refrigerator and voila - it works and give the right readings all the time. I have tested this for 8 months now and comparing with other types of measurements - the last bottle is now 4 months old (open) and still give the same result as my other tests (and a brand new opened bottle)

My findings - Store the open reagent bottle in a refrigerator, shake before use, It works with the cold reagent directly taken from the refrigerator

Other way to handle the test is to always use the same vial, use the same syringe and tip and clean the vale now and then with citric acid

Edit - the period I had tested it - checked my logs - it was 8 months not 6

Sincerely Lasse

Thank you, Lasse

I told Hanna that their older open alk reagents produce high readings, but was pretty much blown off.

Moving to the fridge...

 

[Dan_P]

There is a way to hinder the Hanna alk to show lesser and lesser dKH (or ppm for that matter) with age of open reagent bottle. I had the same story as many have reported here - my reading decrease from a new open bottle with time. Double check with another method show that there was not a real decrease - only that the reagent did not give the colour it should. Comparing with a fresh newly open bottle confirm the false readings of the old reagent. I did a test with shaking the bottle every time I use it - not better result. After this I start to store all open bottles in my refrigerator and voila - it works and give the right readings all the time. I have tested this for 8 months now and comparing with other types of measurements - the last bottle is now 4 months old (open) and still give the same result as my other tests (and a brand new opened bottle)

My findings - Store the open reagent bottle in a refrigerator, shake before use, It works with the cold reagent directly taken from the refrigerator

Other way to handle the test is to always use the same vial, use the same syringe and tip and clean the vale now and then with citric acid

Edit - the period I had tested it - checked my logs - it was 8 months not 6

Sincerely Lasse

This is a clever solution.

What made you think of trying it?

Dan

 

[Lasse]

This is a clever solution.

What made you think of trying it?

Dan

The age of 72

Sincerely Lasse

 

[James Tucker]

There is a way to hinder the Hanna alk to show lesser and lesser dKH (or ppm for that matter) with age of open reagent bottle. I had the same story as many have reported here - my reading decrease from a new open bottle with time. Double check with another method show that there was not a real decrease - only that the reagent did not give the colour it should. Comparing with a fresh newly open bottle confirm the false readings of the old reagent. I did a test with shaking the bottle every time I use it - not better result. After this I start to store all open bottles in my refrigerator and voila - it works and give the right readings all the time. I have tested this for 8 months now and comparing with other types of measurements - the last bottle is now 4 months old (open) and still give the same result as my other tests (and a brand new opened bottle)

My findings - Store the open reagent bottle in a refrigerator, shake before use, It works with the cold reagent directly taken from the refrigerator

Other way to handle the test is to always use the same vial, use the same syringe and tip and clean the vale now and then with citric acid

Edit - the period I had tested it - checked my logs - it was 8 months not 6

Sincerely Lasse

I thought about trying this. I ended up only using 1/2 bottles. I'll do this from now on. Thank you!

 

[uninformed]

I just had this exact problem happen with my last two batches of reagent. Both times, the new reagent tested 1.2-1-4 dKH higher than the old reagent. Last time, I chalked it up to a loose connection between the syringe and the tip on the old set. This time, I tested both syringes/tips on the new reagent bottle and was within 0.1.

Into the fridge mine goes. I’ll report back with the next bottle.

 

[gbroadbridge]

My findings - Store the open reagent bottle in a refrigerator, shake before use, It works with the cold reagent directly taken from the refrigerator

Other way to handle the test is to always use the same vial, use the same syringe and tip and clean the vale now and then with citric acid

Edit - the period I had tested it - checked my logs - it was 8 months not 6

Sincerely Lasse

FYI, This is what Hanna Tech support told me.

 

[Lasse]

Thank you for the information

I did not know what they recommend - but my problems disappear after I start to store it in my refrigerator. Everyone does the way they want - and I hope that the people in this thread that have start to do the same will come back with feedback how it works for them. If I should store it in a cold place as they say in their recommendations - the refrigerator is the only thing that is cold in my apartment.

Sincerely Lasse

 

[Lasse]

My result today - Hanna Checker - 7,28 dKH (130 mg/L CaCO3). Tropic Marine alkalinity pro 7.3. This with a 2 month old bottle and stored in the refrigerator.

Sincerely Lasse

 

[gbroadbridge]

Thank you for the information

I did not know what they recommend - but my problems disappear after I start to store it in my refrigerator. Everyone does the way they want - and I hope that the people in this thread that have start to do the same will come back with feedback how it works for them. If I should store it in a cold place as they say in their recommendations - the refrigerator is the only thing that is cold in my apartment.

Sincerely Lasse

Mine's in the fridge too

The main interesting point is they say 3 to 6 months once open, despite the use by date. The warmer the faster it goes bad.

Regards

 

[Lasse]

It seems that there is rather many people using the fridge for the moment. In 4-6 months - we will know if it is relevant for more than me. I hope so because the Hanna checker alkalinity meter is very good to use - fast and accurate if the reagent is good. If such a easy trick can help to prolong the lifetime of the reagent - that should be very fine.

I hope people will give feedback in this thread - a bad feedback is as good as a good feedback

Sincerely Lasse

 

[tritonpower]

Thanks a lot Lasse. I have had 2 bottles in the last 6 months "go bad". Like you, my reading were low. They did not make sense to have drastic drops in Kh despite my dosers working fine. I checked with my salifert testers and they were low. Today my house tank /garage tank read 8.0/7.6 on Hanna and 8.9/8.4 salifert. I will dump this solution and start using the fridge method. I test both tanks weekly and will give feedback in 4-6 months to see if if happens any more. Thanks again.

 

[Lasse]

Feed back. Open bottle stored in fridge for1 1/2 month - 7.1 dKH. Newly open bottle - 7.1dKH

Sincerely Lasse