Pinpoint no3

[gdemos]

Anyone using these successfully?
I tested with two salifert kits and I get 2 maybe 5 ppm

I test with a calibrated pinpoint (and calibration is hit or miss) with new fluid sent by Lou and on a monitor checked by Lou and I get 10-14 no3-n (over 45 ppm no3)

What gives?

Test calibration fluid with salifert kit
Vial on left is calibration 1ppm
Vial on right is my tank sample

 

[Randy Holmes-Farley Verified Community Expert]

I used a Pinpoint Nitrate Monitor about 10 years ago. I'm not sure if it is identical tot he one sold now. IME it seemed OK, but a fair amount of work to get each reading (similar to a test kit).

I'm not sure what the issue is with yours.

Which concentration of calibration fluids did you use?

 

[gdemos]

These pics show me testing the 1ppm calibration fluid with salifert

I did not bother testing the 10 or 100ppm fluid with salifert; suppose I could but ...

Calibrating the probe is a major challenge. The other day I was able to calibrate the low setting, tested my tank and it read 10...which correct me if I'm wrong but that is approx 44ppm no3.

I have not been able to calibrate since

This thing usually sits in my closet because of the difficulty I have in getting calibrated and the concern I have that it is inaccurate. I suppose I was asking for trouble pulling it out of the closet again

Lou verified some time ago that the monitor and the probe were okay. He must have the magic touch! For a $200+ item this thing should work without fail.

 

[Randy Holmes-Farley Verified Community Expert]

I was wondering which calibration range you used to get the 10 ppm nitrate reading, and whether you get that on both ranges.

That said, if you cannot calibrate properly and get roughly correct answers from the calibration fluids, then something is wrong, but we can't really know what.

FWIW, I didn't use mine much.

 

[gdemos]

Got that 10 on the low setting.
Ironically I was able to get the high setting calibrated and tank tested at 13.

I know better than to freak out about it but still unsettling.

 

[Randy Holmes-Farley Verified Community Expert]

I'd also try the Pinpoint on some new salt water and see if you get a properly low reading from it.

 

[gdemos]

Will do[emoji106] IF I can get it calibrated again!