I never used pharmaceutical grade. Not muriatic acid either. I use something that we here call "salt-acid". I get it at the hardware store. It is used for washing brick walls and such. Diluted down to 4% makes it perfect for activator.
If a datasheet on your product is available it should say plain HCL, which is hydrochloric acid. Nothing else, no additives, no color.
What I have is 30% and not for kids to play around with. Ask again if you have the slightest doubt on how to dilute down to 4%
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