Hanna Phos Meter

[bb]

I've used one for awhile now and have always thought the results were questionable. So I took a few sample today.

Tank Water-.31
Ro Water(Brand New Filters, Spectra Pure) .18
Salt Mix-.23

Tested the tank with Salfert test kit .1-0..

Has anyone else experienced the unreliability with this tester?

[julie180]

Yes. I test at least a couple of samples before I trust the results.

[reefmutt]

yeah, i'm not sold on these devices..
i see a huge variance as well..
i dont own one but i know plenty of people who do and the results are all over.
i find that you end up questioning the high results and believing the low ones..
regardless of which is true..
ill probably stick to my Red Sea and D-D test kits...

[jbfloor]

Mine has been fairly stable, but make sure you clean the crap out of the vials, inside and out. Any fingerprint on the outside of the glass or air bubbles inside will throw off the result. The short timeout on the Hanna meter can be annoying and some people recommend using both vials, one for the clean water and one for the water with powder, but that may throw off the calibration of the test and get you incorrect results. I use a clean towel to completely clean the vial, check for bubbles and undissolved particles before I put it in the meter. I do this before calibration (C1) and again before the measurement (C2)