Fauna Marin Multi Reference bad batch?

[USMA36]

How likely is it to get a bad batch of fauna Marin multi reference solution? I just got the 100ml bottle to test all my Hanna checkers. Nitrate should read 10 it read 0 on 3 tests, Alk should be 6.6 but read 5.3, 5.4, and 5.3 again 3 tests. Phosphates seemed ok. Supposed to read .2 read .22 for 2 tests. Salinity was supposed to read 35ppt Milwaukee read 36 on 4 tests Milwaukee digital refractometer. I’m at a loss.

 

[Dan_P]

How likely is it to get a bad batch of fauna Marin multi reference solution? I just got the 100ml bottle to test all my Hanna checkers. Nitrate should read 10 it read 0 on 3 tests, Alk should be 6.6 but read 5.3, 5.4, and 5.3 again 3 tests. Phosphates seemed ok. Supposed to read .2 read .22 for 2 tests. Salinity was supposed to read 35ppt Milwaukee read 36 on 4 tests Milwaukee digital refractometer. I’m at a loss.

You will need to calculate the +/- accuracy for each result before determining whether the result is outside the Checkers expected result range.. The only result that seems bad is the nitrate. This might be a result of a bad batch of Checker reagent.

 

[gbroadbridge]

How likely is it to get a bad batch of fauna Marin multi reference solution? I just got the 100ml bottle to test all my Hanna checkers. Nitrate should read 10 it read 0 on 3 tests, Alk should be 6.6 but read 5.3, 5.4, and 5.3 again 3 tests. Phosphates seemed ok. Supposed to read .2 read .22 for 2 tests. Salinity was supposed to read 35ppt Milwaukee read 36 on 4 tests Milwaukee digital refractometer. I’m at a loss.

The Milwaukee is +/- 2ppt so that is within spec.
I'd test Nitrate and Alk with a different test to see which test is closer.

 

[GARRIGA]

Hobby level test kits aren’t precision accurate and why I depend on trends vs exact numbers.

Only valid way to confirm reference material is correct is to buy another and/or buy a different type of test such as titration in this situation or create your own reference material. For example, fresh saltwater based on weight of salt added to get 35ppt and not scoops or using a known nitrogen source that can be relied on to create an exact or close enough value for nitrate. I did this once with ammonium chloride to validate API ammonia test strips. Oddly, they were pinpoint accurate although it is well documented by others their titration will always show a value even when it is zero. Go figure

 

[Randy Holmes-Farley]

Aside from testing issues, I've also not seen any detailed analysis of the Fauna solutions.

Maybe they are both off. lol

Makes one feel like we are in the dark, with our hand out in front of us to prevent colliding with something unexpected.

 

[ingchr1]

Aside from testing issues, I've also not seen any detailed analysis of the Fauna solutions...

Externally tested, that's a good question. They state the following:

"With Fauna Marin Multi-Reference Solution, you can test your home test kits under accurate conditions. The Reference Solution is the first to be based on a saltwater matrix and is quality tested using Fauna Marin's ICP-AES testing machine."

 

[Randy Holmes-Farley]

Externally tested, that's a good question. They state the following:

"With Fauna Marin Multi-Reference Solution, you can test your home test kits under accurate conditions. The Reference Solution is the first to be based on a saltwater matrix and is quality tested using Fauna Marin's ICP-AES testing machine."

Since icp does not detect alkalinity or nitrate, that isn’t very useful in this context.

 

[GARRIGA]

Since icp does not detect alkalinity or nitrate, that isn’t very useful in this context.

Keeping it simple. What's wrong with making your own batch of salt to manufacturer's recommendation for know values and using that as your reference? For example, if X brand guarantees 440 calcium at 35 ppt based on grams/Liter then how off could one possibly be or need to spend money on having another source it.

Excluding nitrates or phosphates or other items not part of that salt solution.

 

[USMA36]

The concerning one was the alk. My Hanna was saying 8 my apex 7.8 when used the multi reference Hanna was 5.3 a full 1.3dkh lower than what was supposed to be in the bottle. I ended up opening my next trident reagent box and used their calibration solution in the Hanna alk checker. It was dead on using that solution. That made me feel better. Had the multi ref been correct my tank dkh would have been 6.7. I’ll contact fauna marin. For 20.00 per 100ml I would expect tests to be atleast accurate within 5-10%.