Calbrating Ph meters

[axl]

Hi,
i think my digital ph meter is out because its saying that my water is at 7 but i did a manual test and that come up with roughly 6.8 and i was wondering how do you calbirate them again and i dont have any solution left. ie disattled water
axl

[Merrilyn]

I'm not sure if distilled water would work.

You can buy the calibration solution from some of the larger fish shops. It's not expensive. I think I got my last bottle from Age of Aquariums, one of the sponsors of this site.

[merman]

You need to get your hand on a buffer solution one for pH 7 and one for pH 4 and calibrate that way.

[leanne31]

I got mine from a hydroponic shop $9.95 for a 500ml bottle.

Leanne

[DR.V]

I just asked my lfs to adjust it for me.