Is it ok to use 25 mL NitraVer® 5 Reagent Powder Pillows if the Hach Method specifies 10 mL powder pillows?
Using 25 mL NitraVer® 5 reagents with a 10 mL method
The chemistry of the cadmium reduction powder pillows is sensitive to pH and shaking. The ratio of acidic buffers in the 10 mL powder pillows is not the same as the ratio of acidic buffers in the 25 mL powder pillows. Thus, the amount of color change is different and the instruments are calibrated differently to account for this. Using the wrong size sample and powder pillow will likely give inaccurate results, especially when using the NitraVer® 5 reagents. Therefore, Hach does not recommend using 25 mL NitraVer® 5 Reagent Powder Pillows it the required reagent in the Hach method specifies 10 mL NitraVer® 5 Reagent Powder Pillows.