Quote Originally Posted by georg16nik View Post
red cap APH09 and the blue cap APH09 got potassium hydroxide in it.
The .pdf from Adox site say so, as well http://www.adox.de/ADOX_APH_09(E).pdf
I have measured above mentioned pH levels many times with proper equipment.
All versions of Rodinal contain Hydroxide, right from its introduction however most of it reacts with the metabisulphite to form Sulphite, and the Calbe version has no excess Hyrdoxide.

Section 9 of the PDF you've linked to clearly states the pH of the APH09 concentrate is 11.8, unless you add more Hydroxide it can't go higher with dilution.

Ian