Alk off?
- Thread starter svreef
- Start date
I find I usually need to recalibrate my Trident a couple of times per reagent set, not sure what you mean by recent. If you have test kits you trust more, you can recalibrate to the values the test kits give you while leaving the Trident sample tube in the tank water.
You can also test the Trident calibration solution with your Alk test kit of choice to see if it comes out as expected and if you can rely on the test kit values, but it uses quite a bit of it up.
You can also test the Trident calibration solution with your Alk test kit of choice to see if it comes out as expected and if you can rely on the test kit values, but it uses quite a bit of it up.
You can calibrate against your tank water if you trust your measurements from another source (Hanna, Aquaspin, etc). Calibration fluid has to be used within 8 hours of opening (supposedly; I'm sure the actual time is longer but not sure).
For what it's worth, I calibrated mine for the first time recently (didn't calibrate when I started using it). 0.7 dkh difference between Hanna and Trident pre-calibration, 0 afterwards.
I'll calibrate whenever I use a new bottle of alkalinity test reagent now.
I’ve done both. If you tightly seal the calibration fluid container after first use it stays accurate.
But testing your tank water with testers you trust and then calibrating your trident to those numbers while leaving the sampling tube in the tank is easy and works well for calibration too.
If I had a consistent difference like that I’d be fine with mentally compensating for it, but for me it actively drifts. And not in any particularly predictable frequency, rate, or direction.
Your differentiation of the terms is scientifically correct but since there is no “perform normalization” checkbox in Apex but there is “perform calibration” I used the term that is there so as to not make it more confusing. From the Apex and Trident’s perspective it’s the same anyway.
I use the calibration fluid preferentially each set, but there isn’t enough to run it multiple times as the readings drift. But I have lots of tank water, and my other ways of testing the tank water seem more accurate and don’t drift, including testing them against the Trident calibration solution as I recall.
We are just doing the best we can with what we have.
Vhuang168
Guest
The only way to compare readings across different test kits and devices is to test them against a known solution. A reference solution from ATI or Fauna Marin or our own calibration solution.
Your tank water is an unknown. That is the value we are trying to determine.
Each test kit/device also has its own +/- accuracy range.
The Hanna alk is +/- 5% of reading.
The Hanna Ca is +/- 6% of reading and you need to use high purity distilled water, not RODI.
Any manual test kits are subject to your eye and the surrounding environment.
Your tank water is an unknown. That is the value we are trying to determine.
Each test kit/device also has its own +/- accuracy range.
The Hanna alk is +/- 5% of reading.
The Hanna Ca is +/- 6% of reading and you need to use high purity distilled water, not RODI.
Any manual test kits are subject to your eye and the surrounding environment.