You were on the money Chuck, pH of the second batch had dropped to 2.9 but the gravity was still 1.050 from a start of 1.090.

So I treated it with Potassium Carbonate and got it back to 5 then pitched some additional yeast put in an immersion heater to get the temp back to 25
oC and restarted the thermostat in my hot box to keep a constant ambient atmosphere.
It's bubbling away nicely now but I'll keep an eye on it.
Both 50lt washes were TPW but I decided to experiment a little and while both had 12kg of sugar and two tins of tomato paste and both started off with a pH of approx 5.4 with water from the same source but I put a yeast bomb, as per Capt C's recipe, in the second one.
Evidently the additional nutrients were an overdose that sent the pH to the floor and even though the wash kept on bubbling slowly it was stalling - lesson learned

e.g. If it's not broken don't fix it
Hopefully the second TPW will finish properly sometime this week - maybe!
AM
