ph meter question - Chemists Corner

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ph meter question

Posted by esthetician922 on May 20, 2020 at 10:36 pm

I bought the Apera ph meter. I calibrated it. It reads the 7.0 water solution but when I put it in a thicker serum it doesn’t just stay on one number it fluctuates a lot. thoughts?

esthetician922 replied 4 years, 7 months ago 4 Members · 12 Replies
12 Replies

OldPerry

Member
May 20, 2020 at 10:51 pm

Is it an emulsion or water based formula?
esthetician922

Member
May 20, 2020 at 11:29 pm

good question. it has water in it but then humectants like pca and glycerin

I don’t know exact measurements because I didn’t make it.
OldPerry

Member
May 20, 2020 at 11:31 pm

Does it have oil in it and any emulsifiers? maybe you could list the ingredient list.

But in general, the pH meter may fluctuate a little in the beginning, but it should come to equilibrium and stop moving. If it is an emulsion, then it might not get completely steady.
esthetician922

Member
May 21, 2020 at 2:41 am

water
mandelic
lactic
Sodium Hyaluronate
niacinamide
sodium pca
soidum lactate
glycerin
witch hazel extract
licorice extract
Xanthan Gum

@Perry
OldPerry

Member
May 21, 2020 at 2:59 am

With that list, it shouldn’t jump around.
esthetician922

Member
May 21, 2020 at 3:43 am

@Perry
what ph meter do you recommend then because this one still reads the calibrating solutions correctly but is jumping all around my acid serums.
ozgirl

Member
May 21, 2020 at 3:58 am

How much does it fluctuate? Is it just the decimal place jumping back and forth between two numbers (eg. 4.1 to 4.2) or does it just take a long time to reach a reading.

We have found that some some of our products with low levels of ethanol take a while to reach a stable pH reading. Does your witch hazel have any ethanol?
esthetician922

Member
May 21, 2020 at 4:12 am

@ozgirl
it’ll run up and down from 0-9 it doesn’t stay on or @ a number. I don’t know if the witch hazel has ethanol, I didn’t make this one. If I place it in a toner it sets on a number or even a very runny cleanser but for some reason when I put it in an acid serum it goes crazy.
ozgirl

Member
May 21, 2020 at 4:25 am

That is very strange. Sorry I don’t have any other suggestions. Maybe try contacting the manufacturer.
esthetician922

Member
May 21, 2020 at 4:26 am

@ozgirl
thanks for your help!
Graillotion

Member
May 21, 2020 at 7:03 am

I bought this one:

https://www.saltwateraquarium.com/checker-plus-ph-tester-hi98100-plus-hanna-instruments/

After reading some of the comments on this site…and have been happy with it. There is also a cheaper $29 version of it….on the same site.
esthetician922

Member
May 21, 2020 at 8:50 pm

@Graillotion
awesome! I was totally looking at that one. Thank you.