Jestersix

Alkalinity test kits

Which test kits do you use for Alkalinity?

  • Salifert

  • Red Sea

  • Neptune Trident

  • API

  • Aquaforest

  • Hanna

  • KH Guardian


Results are only viewable after voting.
I had salifert, and then hot Hanna as well, but now my Hanna consistently shows 2-3dKH lower than Salifert + Red Sea.
So now I'm back to Salifert.
 
Checked with a test at the LFS as well.
Doesn't answer my question. All you have confirmed is that 3 tests have similar results to 1 that doesn't. All 3 tests ( I assume the LFS uses similar tests requiring a visual confirmation) have 1 thing in common, us. If you truly want to know, get a known sample (either a reference solution or some kind of calibration solution) and use it on all your tests. The best test is NOT to look at the number on the label and test blindly. Give 3 people 3 different tests using the same known sample.
 
Doesn't answer my question. All you have confirmed is that 3 tests have similar results to 1 that doesn't. All 3 tests ( I assume the LFS uses similar tests requiring a visual confirmation) have 1 thing in common, us. If you truly want to know, get a known sample (either a reference solution or some kind of calibration solution) and use it on all your tests. The best test is NOT to look at the number on the label and test blindly. Give 3 people 3 different tests using the same known sample.
Makes sense, to use a known solution. Also, Checked 4x fresh saltwater mixes for the Alk at given SG as per the manufacturer, and again, Salifert and Red Sea were within 2-8% error over the 4 batches. Hanna was consistently lower.


I have thought about making my own photometer for all Ca/Alk/Mg together, just having trouble finding known calibration solutions (multiple concentrations) for each of them.
 
How much lower?

It surprising how often we do what I call biased corrective actions.

"Should be 8 dkh, but this is not there yet, maybe I didn't see the change, lets drop 1 more. Hmm.. did I see it? Maybe 1 more. Ah... maybe 1 more. There it is. Yup, 8 dkh. Awesome".
 
How much lower?

It surprising how often we do what I call biased corrective actions.

"Should be 8 dkh, but this is not there yet, maybe I didn't see the change, lets drop 1 more. Hmm.. did I see it? Maybe 1 more. Ah... maybe 1 more. There it is. Yup, 8 dkh. Awesome".
Consistently 2-3 dKH lower - all tests were done while not looking at the chart or the graduations on the syringe. Only color change.
 
Back
Top