What type of Hydrochloric Acid to use as activator?

It looks like it's 31% hydrochloric acid. At that strength it is very dangerous to handle. But yes, it should work just fine, in my opinion. Avoid the vapors and wear gloves. Dilute it in a well ventilated space (I do it on my patio).

Thank you for your response, I will be very careful when mixing. 

Could you pass along where you got that.  KVlab seems to be gone now and I can't find activator to continue my treatments.
 Thanks, Steve 

Hi Steve,
I found this particular Product on Amazon. I think it’s a little To Expensive, if you look around you might could find a better supplier. You will have to mix with distilled water to reach the 4% dilution