Inconsistency in hanna alk reagent

Jakepen · May 15, 2021

I have two bottles of reagent, bought at the same time. One tests at 7.0 and the other at 8.3. Multiple tests, same results. Anyone else experience this much difference in bottles?

jgirardnrg · May 15, 2021

take a sample of each in a clear container and check the colors. I was told by Hanna that the bad batches are more yellowish and the correct should be green.

lost66 · May 15, 2021

same here. Alk is the most important parameter and has to be stable and the best solution to measure it is so inconsistent.

saltyhog · May 15, 2021

Jakepen said:
I have two bottles of reagent, bought at the same time. One tests at 7.0 and the other at 8.3. Multiple tests, same results. Anyone else experience this much difference in bottles?

That certainly implies a bad reagent bottle to me. I have not encountered that problem since they changed the seal at the top of the bottle. The old foil seal caused the reagent to go bad if stored horizontally. Since they changed that I haven't had issues.

I would have a friend check your alkalinity to try and determine which bottle to throw away. Have you contacted Hanna about this? Has either bottle been opened for a long time?

Jakepen · May 16, 2021

saltyhog said:
That certainly implies a bad reagent bottle to me. I have not encountered that problem since they changed the seal at the top of the bottle. The old foil seal caused the reagent to go bad if stored horizontally. Since they changed that I haven't had issues.

I would have a friend check your alkalinity to try and determine which bottle to throw away. Have you contacted Hanna about this? Has either bottle been opened for a long time?

I just sent a message to Hanna. Both bottles bought and opened within a week. I have another bottle on hand, I’ll use that one today against the other two. Not going to adjust my dosing, I’m sending out a icp test tomorrow so I’ll wait until I get those results back to see where my alk actually is.