PH probe calibration ???

[wetone]

'I have a Pinpoint PH meter. It is probablt 5-6 years old. It was stored for about 3 years when I had tanks shut down. I have had it in service again for about 10 months. It is way out of whack, showing a PH of 8.5-8.9 while 2 different Salifert test kits show 8.3
My question is how do you "calibrate" it by just sticking it into a known solution? there are no adjustment screws or anything?
Also would I be better just buying a replacement probe because of its age?

 

[wetone]

^^^

 

[slowest is fastest]

True after a year the probe probably could stand to be replaced. Unless the probe was stored properly (kept wet in calibration solution) it will definately need to be replaced.
After you get a new probe remember to buy the calibation fluids. pH 7 and pH 4 are the two I use (although you could also use 7 and 10) Rinse the new probe in Ro/di water and dip it into the ph 7 solution, turn the calibration screw until the monitor reads exactly 7 then rinse and dip into the pH 4 solution and again turn the screw until it reads exactly 4 continue checking between solutions until no further adjustment is necessay to have the probe read correctly in the calibration solutions.
HTH
SiF
PS Draxx looks like we have better weather now...I will send you an e-mail.