In my experience Hanna Checkers require a lot of care and "mindfulness" (?). You need to pick a process that works and stick to it. Then you get your trend line and you can build confidence with your tests. Always have salifert for your more frequent tests -- harder to flub in a hurry.
I do this now:
I do this now:
- Glass clarity on the cuvette -- I now use white cotten gloves to handle the cuvettes----I found if I have scratches on the glass then my readings will go hairy and I toss them and buy new glass cuvettes.
- Wipe down with clean microfiber cloth
- Rinse out only with RODI water/distilled water using a lab safety wash bottle (it gives a nice hard stream) -- rinse the inside cap as well
- Batteries -- replace every year
- Buy the Standards Kit for each checker to ensure the readings are within range
- Make sure nothing gets into the hanna checker itself -- keep lid closed
- Use a 10ml syringe and use the same one always -- don't rely on the line of the cuvette
- Cutting reagent pouches -- always cut the same way, and give yourself time to gently tap the powder directly into the cuvette
- Be sure to rock the fluid after shaking your reagent powders in the cuvette to catch large bubble, and use the extended long press timer on the checker to let small bubble dissipate.
- Never use the Hanna Calcium checker, The Magnesium checker, and the low range Nitrate Checker, pH checker -- these have too many variables and tests are hard to trust...even the pH checker I thought would be easy has a terrible drip mechanism where it's too hard to match drop size every time -- spend the money on a pH probe, in fact, two pH Probes for verification.
