The borax is the same that you find in the laundry aisle of the supermarket. I get the 20 Mule Team Borax and use some for glasswork and the rest in my laundry.
A little of the baking soda or the borax goes a long way.
I know that many people are searching for the holy grail of colored bubbles and the idea of mixing enamels in with the “bubble powder” seems like a good plan. Enamels, essentially ground glass, when incorporated well with the bubble juice, will melt in. Brilliant idea,