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

[Lasse]

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

 

[DeniableArc]

There is a way to hinder the Hanna alk to show lesser and lesser dKH (or ppm for that meter) 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 1/2 a year 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

Sincerely Lasse

Great information Lasse! My reagent will be going in the fridge as soon as I finish this message.

 

[Hermie]

Great information Lasse! My reagent will be going in the fridge as soon as I finish this message.

same but I use API kh test I hope it's the same stuff lol

 

[Lasse]

I also does like this. But I did that way before the refrigerator idea without any better result.

Sincerely Lasse

 

[olonmv]

Saw a video on YouTube about always being consistent on test procedure. Since watching the video I always do the same procedure for all my Hanna checks.

I always fill the vile to where the bottom of the meniscus is always on the line, each kit comes with 2 culvets, I pick one from each and use it every time, and I always insert the culvet with the 10ml facing forward.

Since going with this process I’ve gotten really good consistent readings…..especially with the calcium test which was always sketchy.

Storing liquid reagent in the fridge will be another step to add!!!

 

[Jeeperz]

This should be a sticky.

Wonder if storing other test kits in the fridge will extend their life. I have an old red Sea alk that measures close to a new one even though it's over a year expired and not stored in a fridge but a hot/cold garage

 

[hart24601]

Wow you saved a lot of people issues with this thread. Myself included. Thank you.

 

[EricR]

Wow you saved a lot of people issues with this thread. Myself included. Thank you.

Yeah,,, hopefully.
My Hanna alk reagent just went into the fridge today,,, right after tank test. (It was brand new 10 days ago so we'll see how long I trust it for)

Like someone else mentioned above, I wonder if other brand alk reagents have the same issue after being opened so would also benefit from being kept in the refrigerator. I also wonder if other Hanna reagents have the same issue but haven't seen reports like this aside from alkalinity.

 

[gbroadbridge]

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 1/2 a year 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

Sincerely Lasse

Presumably you then have to let the sample warm up again?

The specs do state the tests to be run at 25 deg C and I would expect the refrigerated reagent would drop the temp by a couple of deg C.

Graham

 

[mdb_talon]

Very good idea. Would add though there are many reports(and i have firsthand experience) with brand new bottles consistently giving readings that differ my 2+dkh. I think the reagents do go bad too quickly and the fridge is a good idea, but i also think hanna needs to step up and give a consistently good product.

 

[EricR]

Presumably you then have to let the sample warm up again?

The specs do state the tests to be run at 25 deg C and I would expect the refrigerated reagent would drop the temp by a couple of deg C.

Graham

Fill the syringe, put the reagent back in the fridge, hold the syringe in your hand to heat it up? ...I don't know,,, good point though

 

[Lasse]

All that start to have the reagent in refrigerator after this thread - please report back in this thread. It has worked for me - but it is interesting to know if it works for more people.

Presumably you then have to let the sample warm up again?

The specs do state the tests to be run at 25 deg C and I would expect the refrigerated reagent would drop the temp by a couple of deg C.

As I wrote before - I have not need to warm it up - directly out and test. My water is 25 degree C. The reagent - let us say 10 degree C. You mix 10 ml 25 degree C with 1 ml 10 degree C. It is 11/1- My test temperature will be around 23,7. I have not seen any effect when I compared refrigerator stored reagent and a new reagent. If I get difference - it follow the given accuracy. If you run your aquarium between 26 degree C and 27 degree celsius (between 78.8 to 80.6 F) it will be around 25 degree when you have add the cold reagent

I have another trick that can be good to know. I calibrate my refractometer with 35 PSU standard but suddenly after some calibrations and when I open a new standard - my salinity was not 35 psu - it was 40 psu. I saw a brand that delivery their standard in a syringe and a cap on that syringe. Brilliant - that way will it not be any evaporation and the salinity of the standard are maintained. I buy that brand but if I can´t get that brand - I take a empty syringer and fill that up with the standard

Sincerely Lasse

 

[xiaoxiy]

@Lasse . I’ve noticed a similar pattern with my Hanna dKH reagents after a month opened too. Good to know refrigerating it slows down degradation. I’ve been throwing out left over reagent monthly, so you’ve saved me some future $$.

 

[Lasse]

so you’ve saved me some future $$.

I hope so

Sincerely Lasse

 

[StewL6]

Has anyone reported the need to refrigerate back to Hanna for their response I would love to hear it.

 

[atoll]

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 1/2 a year 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

Sincerely Lasse

Good advice my friend

 

[Lasse]

Has anyone reported the need to refrigerate back to Hanna for their response I would love to hear it.

Nope - not me

Sincerely Lasse

 

[Jeffbear]

Thank you for this! I will start doing this with the new bottle I open this evening.

 

[Reef.]

All that start to have the reagent in refrigerator after this thread - please report back in this thread. It has worked for me - but it is interesting to know if it works for more people.



As I wrote before - I have not need to warm it up - directly out and test. My water is 25 degree C. The reagent - let us say 10 degree C. You mix 10 ml 25 degree C with 1 ml 10 degree C. It is 11/1- My test temperature will be around 23,7. I have not seen any effect when I compared refrigerator stored reagent and a new reagent. If I get difference - it follow the given accuracy. If you run your aquarium between 26 degree C and 27 degree celsius (between 78.8 to 80.6 F) it will be around 25 degree when you have add the cold reagent

I have another trick that can be good to know. I calibrate my refractometer with 35 PSU standard but suddenly after some calibrations and when I open a new standard - my salinity was not 35 psu - it was 40 psu. I saw a brand that delivery their standard in a syringe and a cap on that syringe. Brilliant - that way will it not be any evaporation and the salinity of the standard are maintained. I buy that brand but if I can´t get that brand - I take a empty syringer and fill that up with the standard

Sincerely Lasse

The inconsistency of the Hanna alk checker was stopping me buying this checker, I have the nitrate and p04 and rate them, your fridge tip may just push me over the edge to buy one!

Salinity, I use Randy’s DIY method, all you need is plain table salt and a set of 0.01g scales at around $15, then you can make a reference solution as many times as you wish, and know it’s correct.

 

[atoll]

The inconsistency of the Hanna alk checker was stopping me buying this checker, I have the nitrate and p04 and rate them, your fridge tip may just push me over the edge to buy one!

Salinity, I use Randy’s DIY method, all you need is plain table salt and a set of 0.01g scales at around $15, then you can make a reference solution as many times as you wish, and know it’s correct.

Do you have a link to the DIY method