How to adjust mash ph

I got a PH meter last week and used it in a Pale Ale brew.

After mashing in I took a reading and got 5.8.

Using phoisphic acid, how would I adjust this down to 5.3.

A website I came across suggested the following formula to adjust PH.

mL of lactic acid needed = change in pH x weight of grain in lbs.

In my case 8 ml = .5 x 16 and I used phosphoric acid 85 % instead of lactic acid.

So I added about 8 drops of phosphoric acid ( I read that 1 drop is ± 1 ml) but when I tool PH reading again the PH had not changed at all.

Was this because I used phosphoric acid instead of lactic acid ?

Could anyone comment on this and maybe suggest a formula using phosphoric acid.

Bump bump bump

Surely someone can enlighten me ?????

What strength is the phosphoric acid? Most lactic acids are 88%, but my phosphoric acid is like 10%. That means that they aren't a 1-for-1 substitution.

I use this chart for adjusting mash pH: http://braukaiser.com/wiki/index.php?title=Mash_pH_control#Adding_acids
(Scroll to table 3, near the bottom). I keep that chart in my brewing area.

Unless you have very odd water you shouldn't have to add any acid as long as the Calcium content is high enough and the water is balanced correctly for the grist. You do need to know what is in your water as an all-grain brewer. Get a report from your water supplier or have a lab test it for you. Check out the Brew Science section here at HBT for a wealth of brewing water information and links to water calculators.

Wheelspin said:

So I added about 8 drops of phosphoric acid ( I read that 1 drop is ± 1 ml) but when I tool PH reading again the PH had not changed at all.

Click to expand...

There is about 20 drops to a ml.

Big thanks for the responses.

Yooper, the phosphoric acid is 85 % (BTW just bottled your Yoopers Pale Ale - AWESOME !! thank you)

BigEd, I'm attaching what I believe to be the water report for my area but don't know how up to date it is.

Diverpat, so I should have put in about 160 drops ??