Is my PH meter shot?

Im currently using this PH meter: http://www.ezirange.com.au/ezitools/pen-meters-ezi/ .

Its about 2 months old and gets used roughly everyday.

But when i try and calibrate it in Buffer solutions 7 and 4, i cal it to 7 then when i stick it in the 4 it will read 3.5-7 so if i cal it to the 4 the same will happen when i put it back into the 7, it will read 7.5-8.

Im calibrating it so on ether side its about .4 off to try and balance it out but are my attempts futile? Is it broke?

It little glass electrode dosent look dried out or damaged in anyway so i dont know whats up, any ideas?

Thanks for any help.

why would you wanna use it roughly to begin with? makes NO sense man

are u washing off the 7.0 be4 putting into the 4.0 ?, my guess is try getting another source of 4.0 and see if it goes to 3.5 on both 4.0 buffers

lol , he means he uses it everyday

howhighru said:

why would you wanna use it roughly to begin with? makes NO sense man

Click to expand...

Heh i mean roughly as in mostly everyday.

smallclosetgrowr said:

are u washing off the 7.0 be4 putting into the 4.0 ?, my guess is try getting another source of 4.0 and see if it goes to 3.5 on both 4.0 buffers

Click to expand...

Yea im washing and drying it off in between solutions... so yea im stumped.

Keep any ideas coming, thanks.

Ok i contacted my hydro guy and his response was, and i quote, "Hi, these are only a cheap pen, and only have 1 point calibration, you only need to calibrate with buffer 7. Try this, it should work."

Now is that complete bull? Or is there any truth to this?

The instructions that came with the meter read:
Range:0-14pH
And to calibrate the meter with both 4 AND 7 solutions?

So if i cal it to 7 and its reading nearly 3 in a 4 solution, with a rated range of 0-14pH, its faulty yah?

Your testing probe is bad/worn out. I use a different tester that has replaceable probes. I am on my third probe and when all the others went bad I could not calibrate to 4.01

Until i can get a new meter, what would be the most accurate? To calibrate it to 7, 4 or balance it between the two?

i always go solution testing....if you can....i get my ph to my liking...

the hydro guy was right. some pen types do only have 1 point calibration which means the accuracy is pretty loose. use the 7 solution since you are looking for numbers in that range.