A few questions...
What did you use to measure mg?
What did you use to measure exacting ph? Are there strips sensitive enough to measure so accurately?
Your formula says sodium thiosulphite but the linked formula says ammonium thiosulphate which means the active ingredient is the thiosulphate/ite which has a different oxygen structure and has a different activity level, so making sure you didn't mistaking list the wrong compound.
I'm not a chemist but my dad is so I sent him the formula and he asked about the above.
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