In the middle of a Ph crisis.

[Underthethumb]

Chaps,

I would appreciate your thoughts.

7.30am and half way through a mash. Checked Ph after 10 minutes and stands at 4.9! (Previously i've always been between 5.2 and 5.5).

I have double checked my calculations for CRS/DLS and checked the CaCO3 level with a Salifert test kit. I'm pretty sure I measured the water treatment out properly. Ph meter seems Ok giving 6.9 in tap water.

Has anyone any idea why this might have happened? (ignoring the obvious potential for cock-ups on my part). Does anyone have any idea what the implications might be for the beer?

Will check again at end of mash and report back.

Bang goes my relaxing mash time catching-up on 'Match of the Day'. Thanks in advance.

Grain Bill:

Pale Malt 5453
Torrefied Wheat 163
Crystal Malt 392
Wheat Malt 163

Mash Temp: 66.8C

Mashing at 2.5 litres/Kg = 15.4 litres.

DLS at 8.5g/litre (with 8.34g added to the mash)
CRS at 1.12ml/litre

CaCO3 level 245ppm

Target CaCO3: 40ppm
Target Calcium: 200

[Underthethumb]

Final Mash Ph 5.0

[barney]

Is your PH meter calibrated and temperature adjusted?

[PureGuiness]

Is this recipe any darker in colour than previous brews? If so have you tweaked the target residual alkalinity to counteract the acidity if the malt?

[Scooby]

Same has happened to me for the last few brews, I use litmus paper and just blamed them. I must get a new pack

like you I checked all my procedures each time and couldn't fine a reason. How is your mash efficiency in this brew?
This can suffer if the pH is out. My efficiency didn't change in fact I got slightly better in the last brew.

Apart from the effect on the mash efficiency I not sure what other implications are but I can tell you that my beers
tasted just great so I wouldn't worry about it to much.

Edit here are the stats from my last brew;

My water;
Carbonates as CO3 134.4
Chloride as Cl 15
Sulphate as SO4 19.55
Calcium as Ca 61.6
Magnesium as Mg 0.96

Initial Alkalinity 225 CaCO3 reduced in 2 stages to 27 CaCO3

14850g malt for pale ale
37l mash liquor
10.6g calcium sulphate
4.5g calcium chloride
mashed @66c

Mash pH 5mins after dough in 4.9

[Underthethumb]

The efficiency was bang on 75% so hit the target gravity of 1.060. Wort tasted sweet and everything seems normal so far, but time will tell.

Thanks for the advice