Hanna calibration kits

[Reef Pilot]

Originally Posted by DSlater

Do you feel your PO4 readings are high, low, or just inaccurate?

My HI713 always gave higher readings but consistent so I never really questioned. Finally checked against another kit and it was reading way high. Tried my next box of reagent and everything tested at 0.00ppm. Even tap water and rejected water from RODI.

The color test kits will always read zero before the Hanna. They are simply not as accurate at the ultra low range. That's why I got the Hanna.

Some have had difficulties getting accurate and consistent readings from their Hanna Checker. These include not pressing AND holding after C2 until the 3:00 min timer shows on the display. Not using the same vial for both the C1 and C2. Not cleaning all fingerprints. Not getting all the powder out (there are tricks to this). Not mixing properly (you have 3 min and you need to pause to let all fine bubbles dissipate).

Have not seen problems with reagents, but I guess that is possible.

I have been using mine for a couple years now, and it has been very accurate and totally consistent with the readings. I have also personally helped others who have come to my place with their checkers to get theirs working accurately. And have that offer open to anyone else that might be having problems with theirs. Sometimes the issues are not apparent until you see how a person does their testing (many ways to do it wrong).