So Hanna emailed me back very quickly
“Here are some tips the Aquariums manager put together which may be helpful.
Repeatability issues are purely related to the quantity of reagent dispensed. In our experience, it just takes a little bit of practice getting used to dispensing the somewhat viscous reagents, but after a few tests most users get very consistent measurements.
Review the tips and tricks section in the instruction manual carefully. The most common issues and how to prevent them are explained there.
Ensure the cuvettes are rinsed with RODI water thoroughly after use. It must be dry before used again - shake out any remaining RODI water left in the cuvette if repeating measurements.
Ensure a good seal between the syringe and the syringe tip: the liquid should not be dripping out while you are holding the full syringe.
One thing you can try is to push the gasket that is in the dosing tip down further into the tip because as the dosing tip goes down it tapers more which will make a tighter seal.
If liquid remains in the syringe after dispensing the reagent or sample, try expelling it into the cuvette by gently shaking down the remaining liquid to the bottom of the tip, intaking some air with the plunger, then expelling the drop. Repeat if necessary to expel any large drops. Tiny remaining drops will not affect the measurement”
I’m going to humor them and run the tests again, I’m no laboratory technician/chemist, but I don’t think there was any problem with the volume of reagents/sample since I tried multiple techniques to ensure precise volumes were used.
“Here are some tips the Aquariums manager put together which may be helpful.
Repeatability issues are purely related to the quantity of reagent dispensed. In our experience, it just takes a little bit of practice getting used to dispensing the somewhat viscous reagents, but after a few tests most users get very consistent measurements.
Review the tips and tricks section in the instruction manual carefully. The most common issues and how to prevent them are explained there.
Ensure the cuvettes are rinsed with RODI water thoroughly after use. It must be dry before used again - shake out any remaining RODI water left in the cuvette if repeating measurements.
Ensure a good seal between the syringe and the syringe tip: the liquid should not be dripping out while you are holding the full syringe.
One thing you can try is to push the gasket that is in the dosing tip down further into the tip because as the dosing tip goes down it tapers more which will make a tighter seal.
If liquid remains in the syringe after dispensing the reagent or sample, try expelling it into the cuvette by gently shaking down the remaining liquid to the bottom of the tip, intaking some air with the plunger, then expelling the drop. Repeat if necessary to expel any large drops. Tiny remaining drops will not affect the measurement”
I’m going to humor them and run the tests again, I’m no laboratory technician/chemist, but I don’t think there was any problem with the volume of reagents/sample since I tried multiple techniques to ensure precise volumes were used.