Help ph probe calibration

[wil0311]

I just bought a calcium reactor. I have packets of ph calibration solution of 7 and 10. Now I want to run the reactor at around 6.6 ph. So my question is can I calibrate my probe with 7 and 10, or do I need the 4 and 7 solutions? I would like to know if the probe is accurate when lower than 7 ph because I already calibrated it with the 7 and 10 solutions.

Thanks for your help.

[Tom R]

I would calibrate it with 4.0 and 7.0 this will make more accurate at a predominate level of 6.60.

Tom R

[wil0311]

Ok thanks Tom I will order some 4.0 packets right now.

[mark]

might make it more accurate but the slope is probably close enough for a reactor with 7 and 10.

Should try a little experiment with a solution of say around 6.6 or at the least cal with the 7 and 10 and tell us what the 4 comes in at.

[Jason McK]

Typically when using a PH probe to measure your tank PH you Calibrate at 7 and 10. If you are using the probe in a CA reactor you Calibrate and 4 and 7.
The difference is very noticable when using the probe in the reactor. I went from calibrating at 7 and 10 to 4 and 7 and my probe rose 0.4. That is a lot when it come to melting Calcium carbonate

J