Greg Lorriman wrote:

> On 24 Aug, 02:47, wrote:
>> Just to add to the already good advice. The
>> lower the Ph the less SO2 needed. I don't
>> remember the actual amounts but if your Ph is
>> high, say around 3.8-4.0 you need more SO2 in
>> ppm to protect it compared to if the Ph was ,
>> say, 3.2.
>
> Interesting. Where do you get such info? My
> winemaking books haven't led me so far down this
> path.

A "Rule of Thumb" is this for the following pH

pH | SO2 in parts per million

3.2 20 ppm
3.3 30 ppm
3.4 40 ppm
3.5 50 ppm
3.6 60 ppm
3.7 70 ppm
3.8 80 ppm
3.9 90 ppm

In other words, just look at the tenths digit in
the pH and multiply times 100