PH Meter Calibration

[Ontombose]

Hi there hope somebody can help.

I have PH meter for when I set up my marine tank and was advised to get solution 7 and 10 to calibrate the Meter.

I now have the PH Meter, Solution 7 and 10 and now I am really confused.

Do I dip the probe into the solution and then adjust the meter to read 0? and why the two solutions as once it has been calibrated to either 7 or 10 surely calibrating it to another PH mess up the previous calibration:confused::confused::confused:

Thanks for any help it is greatly appreciated..

[alanwsg]

Does your pH meter have dual calibration adjustments?
i.e. has it got two screws or knobs labelled pH7 & pH10?

From your post, I suspect not.

In that case you just put it in the pH7 solution and adjust it so that it reads 7.0, you don't need the pH10 solution.
That's the best you can do.

(More expensive meters, e.g. pinpoint, have adjustments at both pH7 & pH10, it's possible to get more accurate measurements like this, but yours will be good enough and far better than a test kit).

[willjay]

i got the disposable sachets (pinpoint ones) for my meter, i have just one adjusting screw.
first make sure the temp roughly 25 degrees of the solutions, or you know the temp as you can correct on the scale on my solution sachets.

remove from the tank and then rinse the probe i used RO in a jug just to help accuracy - then dry off, with kitchen paper.

then test 4.0 and adjust if needed
rinse
then test 7.0 and adjust if needed
rinse
finally test at 10 and adjust if needed

then I made sure i rinsed off the probe well before returning to the tank.

each solution is different and each reading helps to confirm and calibrate the meter.
in practice after the first reading and adjustment the adjustments i made were tiny and the meter was reading pretty much spot on for the last two solutions

Think what i'm doing is right!

[Ontombose]

That is great guys thanks for the speedy responses.

In future should I will just buy the one solution 7.0 then.

Many Thanks

[willjay]

i see reefdreams do a pack of ten of each solution quite cheap, thats what i;ve got.
I think you might get all three types, i think and they will last ages anyway dude, i calibrate mine every month and still got loads of sachets left!

that way you have three shots at getting the meter accurate and you'll be happy to trust it!
good luck dude:cool:

[CHRIS D]

Willjay,

I'd suggest to callibrate a probe to go in a tank it's only necessary to use 7 and 10.
4 and 7 are generally used to callibrate probes that go in calcium reactors where the pH is much lower.

Chris

[willjay]

ahh excellent Chris, thanks
i'll use the 7 and 10 then