making hcl activator

Can i make my own 4 % HCL activator out of muratic acid? Does it need to be pharmaceutical grade?

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%

Information on using and diluting muriatic acid for activator: www.mmsinfo.org/infosheets/hcl_from_muriatic_acid.pdf