Hi Fidelityboy - thanks for your apology.
Looks like both CLO2 and I may have misspoke too though, and owe you an apology in a way because according to the table we basically approved for Kerri's book, Healing the Symptoms of Autism, 50% citric acid can be used (we must have approved it, right CLO2?), but it's been so long and we both prefer HCl so much that we must have put it out of our minds. Another reason we may have put it out of our minds is because we were both so pissed off at Mark for screwing up the formula so badly. When you see the table for a 550ml bottle you'll understand that by using 25ml of 50% citric acid he completely screwed up the end result and then had no idea of what concentration of CLO2 he had. Kind of like a drunk person making a cake and totally ignoring the recipe we spent so much time perfecting, and then presenting it to the world on YouTube as if it was still the same thing. So attached below is the table for you to see what the correct amount is for a 550ml bottle.
Regarding your question as to what the end concentration is, it's hard to know for sure but since 50% citric acid is about 40% more than 35% and we know if Mark followed the table he would have ended up with 3500 ppm. 3500 ppm plus 40% more is 4900 ppm. But then he also used more than the 22.9ml he was supposed to have used even with the 35% citric acid, and instead he used 25ml of 50% citric acid (when he should have only used 16ml). So because of all that the final ppm is probably something over 5000 ppm. I think you can see why we were so upset with him for screwing it up so badly. And then to add insult to injury, he wouldn't even correct it (to this day).
Hope that helps and you have my apology too.
All the best,
Scott