Nitrate Pro test kit question

[WallysWorld]

I've been using the Red Sea Nitrate Pro Test Kit for a long time (several years). I replace the reagents well before the expiration dates. For a while now I've been getting solid particles in the result vial at the end of the 9 minute wait time. The particles are a dark purple in color and often they are the site for a stream of bubbles forming. This looks a bit like a carbonated beverage stream of bubbles. The particles being a dark purple shade make matching the pink scale difficult, the test solution is completely the wrong tint. I rinse the vials after each test with fresh tap water, and then rinse them several times with tank water at the beginning of every test.

Are the purple particles a normal part of this test? Are my reagents bad? Or is this from some bad testing methodology?

 

[blaxsun]

Weird. Have you tried soaking the glass vials in vinegar for a few hours and then thoroughly scrubbing out? I have the nitrate test kit from the Marine test pack (not sure if it’s the Pro or not), but I’ve never ended up with any particles at the end of the 9-minute mark (at least that I could see anyway).

 

[Spieg]

I've used the Nitrate Pro kit and never experienced this. Seems like something is not right (may be bad reagents or just not shaking the vial enough). I usually store my vials filled with RODI water.