Hanna ULR Phoshate Checker - 3 different readings?

[Mppp]

I just ran 3 tests in a row on my Hanna ULR Phosphate and had 3 different results. (Between .09 2nd test and 3rd I decided to put in a new battery just for heck of it btw)
.18ppm
.09ppm
.21ppm

Has anyone else ran a couple to few tests in a row w/ different ranges outside the margin of error like this on 2nd test?

 

[bradreef]

If you get any particulates in that have phosphate i can get high readings.

 

[Mppp]

How do you know when you have any particulates in your test tube? Are you talking about visually/seeing a piece of food in test vial or similar? I just found a thread where member speaks of battery quality. I'm not sold on battery being the issue, but I've been wrong before?

The AAA batteries of Hanna checkers

Little story: Since my Hanna PO4 URL checker always turned on and appeared to work properly, I always assumed that, despite the glorious reviews, it probably wasn't that great. In fact, according the PO4 URL checker, both my display and my coral quarantine were always a random number between...

www.reef2reef.com

 

[bradreef]

Yes, floating debris

 

[bradreef]

Yes, floating debris

Also. Ensure the tube is clean. Facing the same direction every time you put it in the tester

 

[Reef.]

I would have to say it’s either a faulty checker/reagent or you are not doing the test correctly.

I use the same checker and never have such wide readings.

The margin of error on that checker is only 0.02 I believe.

 

[Mppp]

I would have to say it’s either a faulty checker/reagent or you are not doing the test correctly.

I use the same checker and never have such wide readings.

The margin of error on that checker is only 0.02 I believe.

UPDATE: My wife had mentioned my son had accidentally knocked the checker off the counter while it was counting down when I left the room...this has to be the reason why readings have all of the sudden gone wacky!

I have never had problems before nor can remember the last time I've had readings above .08 (it's been awhile).