is there a solution that i can make to verify alk reagent?

[Miller535]

so I have been using the hannah checker for alk for i dont know, maybe 7 months. And have went through a few bottles of reagent. On fish of hex, he says when you are almost out of one bottle of reagent to test your alk, then right away test your alk again with the new bottle. So i did this today and my alk with the old reagent was 8.5. Exactly what I keep my tank at. Then I used a new bottle at it wad 7.7. What? Ok so I opened another new bottle I had and it was 7.4. So I'm really confused. I go grab my red sea alk test kit, and it reads 7. Have I been wrong all this time? Sure seems so. But I dont want to just react and dump alk in my tank. This got me thinking, is there a way I could make a solution to test my checker reagent. Likr if I mix x amount of brs sodium bicarbonate into y amount of water and it will give me a fixed dkh?

 

[Miller535]

I am assuming if anyone would know it would be @Randy Holmes-Farley

 

[Miller535]

Anyone?

 

[Cory]

Yes 1.135 grams of sodium bicarbonate in 1 gallon purified water (0tds) will equal 10dkh. May or may not work with hanna checker (i haven't tried)

 

[Miller535]

Yes 1.135 grams of sodium bicarbonate in 1 gallon purified water (0tds) will equal 10dkh. May or may not work with hanna checker (i haven't tried)

I will definitely be trying that, thank you

 

[Cory]

I will definitely be trying that, thank you

Good to know. If you dont got a good scale a pharmacist will weigh it for you free ime.

 

[SliceGolfer]

I go about this differently. I always try to purchase multiple reagents from the same lot number. I do the same method when one bottle empties and open another. Here’s where I differ: I compare the difference and add or subtract that value going forward with the new bottle. This way I am maintaining a stable Alk value and adjusting for the variance in the reagent.

For example, I test and get 8.1 and then open a new bottle and get 8.2 for a difference of -0.1. Going forward I subtract 0.1 from all future tests to accommodate the variance in the reagent. Been doing it this way for over a year with very stable results.

Trusting the reagent to be correct, understanding the accuracy changes with exposure to air, and playing the Alk swing game because of the reagent differences I feel can be avoided in this manner.

 

[X-37B]

Hanna has a standard kit that I use. Cost $10.
I have salifert and elos as backup reference.

 

[Miller535]

Good to know. If you dont got a good scale a pharmacist will weigh it for you free ime.

I just bought one on Amazon. Lol

 

[Miller535]

I go about this differently. I always try to purchase multiple reagents from the same lot number. I do the same method when one bottle empties and open another. Here’s where I differ: I compare the difference and add or subtract that value going forward with the new bottle. This way I am maintaining a stable Alk value and adjusting for the variance in the reagent.

For example, I test and get 8.1 and then open a new bottle and get 8.2 for a difference of -0.1. Going forward I subtract 0.1 from all future tests to accommodate the variance in the reagent. Been doing it this way for over a year with very stable results.

Trusting the reagent to be correct, understanding the accuracy changes with exposure to air, and playing the Alk swing game because of the reagent differences I feel can be avoided in this manner.

Your method is my normal method. And from one reagent to the next its usually .1 maybe .2 off. But 8.5 to 7.7 and 7.4 are all very different.

 

[Miller535]

Hanna has a standard kit that I use. Cost $10.
I have salifert and elos as backup reference.

Where do you buy it from?

 

[X-37B]

Where do you buy it from?

BRS

 

[X-37B]

Your method is my normal method. And from one reagent to the next its usually .1 maybe .2 off. But 8.5 to 7.7 and 7.4 are all very different.

Make sure you clean your vials with vinegar every couple months.
Rinse your vials and keep filled with ro/di water between uses.

 

[Cory]

Do not trust store bought standards. Do you really want to assume their standards are correct, like you assume your test kit is?

Just make your own.

 

[Randy Holmes-Farley]

BRS

That is not an alkalinity standard. it is just a color standard to check the device operation. It doesn't confirm the reagents work.

 

[Randy Holmes-Farley]

DIY alk standards:

DIY alkalinity standard

For folks who may want to evaluate the accuracy of their alkalinity test kits, here are two suggested ways to do it. One is DIY and one is a mostly commercial standard with one DIY step. Method 1 Standard solutions could be made with sodium bicarbonate, but it can be hard to be sure it hasn't...

www.reef2reef.com

 

[X-37B]

That is not an alkalinity standard. it is just a color standard to check the device operation. It doesn't confirm the reagents work.

That is not an alkalinity standard. it is just a color standard to check the device operation. It doesn't confirm the reagents work.

Thanks for the correction!
Its been over 25 years since I got out of the chemistry/engineering field.

At least I know my unit is working, lol.

I use Hanna because it's fast and accurate enough for the hobby.
Anytime I get a questionable reading I cross check with salifert.

Keeping the vials clean is paramount.

I just tested alk.
Hanna-123=6.88
Salifert- .55=between 6.7 and 7 going to a pink endpoint.
Close enough for me.

Maybe im just lucky but I have been using the Hanna unit for 3 years now and have not seen a noticable difference from one bottle of reagent to the next like the op did.

When I have seen a difference it has been attributed to operator error, lol.

 

[Shirak]

Thanks for the correction!
Its been over 25 years since I got out of the chemistry/engineering field.

At least I know my unit is working, lol.

I use Hanna because it's fast and accurate enough for the hobby.
Anytime I get a questionable reading I cross check with salifert.

Keeping the vials clean is paramount.

I just tested alk.
Hanna-123=6.88
Salifert- .55=between 6.7 and 7 going to a pink endpoint.
Close enough for me.

Maybe im just lucky but I have been using the Hanna unit for 3 years now and have not seen a noticable difference from one bottle of reagent to the next like the op did.

When I have seen a difference it has been attributed to operator error, lol.

I would like to think operator error too but I can see it would be possible to be shifts in the reagent depending on how fast you use it and perhaps how long you leave the lid off and your local weather etc. I uncap fill the syringe and recap as fast as possible. One note though.. I had one vial I was using and the glass looked like it had a slight blue tinge. Every time I used it the reading was way off from the trident and other test kits including running the Hanna again with a different vial..

I tossed that vial!

 

[X-37B]

I would like to think operator error too but I can see it would be possible to be shifts in the reagent depending on how fast you use it and perhaps how long you leave the lid off and your local weather etc. I uncap fill the syringe and recap as fast as possible. One note though.. I had one vial I was using and the glass looked like it had a slight blue tinge. Every time I used it the reading was way off from the trident and other test kits including running the Hanna again with a different vial..

I tossed that vial!

I go through a bottle a month so its not sitting around for long.
I test 2 tanks.
Display is run by a carx.
Frag/lagoon is esv 2 part.
I dont need to test every day but typically do. Every other day on the frag sysyem and I keep a log. Its cheap enough and works for me.
My vials are 3 years old too.
I clean with vinegar once a month.

 

[Miller535]

I would like to think operator error too but I can see it would be possible to be shifts in the reagent depending on how fast you use it and perhaps how long you leave the lid off and your local weather etc. I uncap fill the syringe and recap as fast as possible. One note though.. I had one vial I was using and the glass looked like it had a slight blue tinge. Every time I used it the reading was way off from the trident and other test kits including running the Hanna again with a different vial..

I tossed that vial!

I am very sure it's not operator error. I use the reagent pretty quickly as I test a lot. I have went through several bottles since I bought the hanna checker. And each bottle tested fairly close to the previous bottle. If the operator was going to test in error, they are likely to consistently test in that same error. And my problem is that from one bottle to the next it was a drastic change.