Hanna Checker Phosphate ULR accuracy

[gbroadbridge]

I have noticed anomalies in the readings me too.
Many times, after dissolving the reagent in the vial, black-colored residues remain.
When these are present, the reading is clearly incorrect.
By now, whenever I see them, I throw the sample away and start over.

The problem is that, even with brand-new reagents from different lots and packages, this happens to me almost one out of every two times.
I have written to Hanna Italy (where I live) and Hanna USA, but I have never received a reply.

I've been using the Hanna phosphate checker since it was released and I in that time (thousands of tests), I have had only one single test that failed.

 

[disaster999]

you guys preach Im doing the test wrong by using 2 vials so I did 2 tests back to back with 1 vial. Sampled clean tank water, added the powder, mixed, wait 3 mins, went for the second reading. One test reads 44 (0.136ppm), while the other at 20 (0.063ppm).

 

[aus1230]

I am having the same trouble. Hanna giving high numbers and Salifert test showing 0. Did you ever find out a resolution?

Hey Lonzo, after getting a bunch of different ideas from it being the vials, reagent, and it even possibly being the unit. I ultimately decided to just purchase a new unit that came with those three things new especially since I bought mine used.