API testing

[PeterEde]

I thought I'd do my test using my original API kit
I've not used it for over 12 months.
I found all results to be within limits.

What I did find is the 5ml mark on the vials to be questionable when using 5ml syringe to add water.

I guess my advice to new aquarist would be get 5ml syringe and don't rely on the 5ml mark on these vials

 

[jabberwock]

An interesting observation. I will do some independent investigation. I have always defaulted to the mark on the vial, and never paid attention to the reading on the syringe.

 

[PeterEde]

An interesting observation. I will do some independent investigation. I have always defaulted to the mark on the vial, and never paid attention to the reading on the syringe.

I believe a medical syringe to be a more reliable measure.
I also verified the 5ml syringe in a scientific graduated vial.

 

[jabberwock]

I believe a medical syringe to be a more reliable measure.

Tend to agree, I use the type that doses liquid medication, so likely not all that reliable. I have access to multiple devices however.

 

[Dan_P]

I thought I'd do my test using my original API kit
I've not used it for over 12 months.
I found all results to be within limits.

What I did find is the 5ml mark on the vials to be questionable when using 5ml syringe to add water.

I guess my advice to new aquarist would be get 5ml syringe and don't rely on the 5ml mark on these vials

The human eye is unlikely capable of detecting the difference in color obtained with fill to the line and exactly 5 mL of sample.

 

[PeterEde]

The human eye is unlikely capable of detecting the difference in color obtained with fill to the line and exactly 5 mL of sample.

Human eye can detect 16 million colours. Yes some may struggle but also in some cases the difference might make the difference. Just an observation all the same.
Is it really so hard for API to mark vials correctly and eliminate the possibility.

 

[Dan_P]

Human eye can detect 16 million colours. Yes some may struggle but also in some cases the difference might make the difference. Just an observation all the same.
Is it really so hard for API to mark vials correctly and eliminate the possibility.

I bet you cannot tell the difference in color between a 5 mL sample and a fill to the line sample. Post some pictures of the experiment.

 

[PeterEde]

Why worry. It was an observation. Let it go

 

[rennjidk]

Are we really arguing fractions of a ml, in a test kit that measures in a "go / no go" fashion?

 

[taricha]

What I did find is the 5ml mark on the vials to be questionable when using 5ml syringe to add water.

I guess my advice to new aquarist would be get 5ml syringe and don't rely on the 5ml mark on these vials

Fortunately none of those tests have volume-sensitive chemistry to create any real difference. or as Dan said....

The human eye is unlikely capable of detecting the difference in color obtained with fill to the line and exactly 5 mL of sample.

But for the titration tests - Alk and Ca, absolutely it matters whether you use the "5ml" line or a different measured 5.0mL syringe.