To raise, I would add water. Lets say you used 3/4lb salt per gallon of water, and 3oz per gallon of citric for the origional pickle. Add a gallon of water, and 3/4lb of salt, to raise the Ph some. You have to add the salt, to keep the concentrations the same. Alot depends on how large the pickle is. If the pickle is 40 gallons, its gonna take quite a bit of bi-carb to raise the pH very much, and you are going to have a BIG FOAMY MESS, trying to raise the pH. Not to mention, you will probablly lose some solution from the overflow, and have to add more water and salt anyway.
To lower, bucknut told everyone how to lower, but, wait for the pickle to stablise, after the addition of skins, so you usually wont have to do it more than once.
KEEP RECORDS! Using the same containers, and the same water sourse, and the same formula, EVERY TIME, will save YOU some time. If your doing deer capes, try to pickle the same amount of capes each time.
Lets say, you like to pickle 5 deer capes at the time. A few hours after adding the capes to the pickle, you see the pH has risen. You have to add acid. WRITE DOWN how much acid you had to add to get the pH where you want it. THEN, the next time you make a new pickle, for 5 deer capes, use your origional formula, PLUS the little extra acid you had to add to get the pH to stabalise, that you wrote down, from the pickle before.
More often than not, the pickle will stabalise out, right where you want the pH to be!
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