Recipes trafficked online seldom include important information. How could the author of this one not mention this problem? The slurry turns to a gel and fills with bubbles. And then you have to add water again. The extra water makes it shrink more, compromising the bond with the bisque so it peels away when overgrazed. Later more water is needed because it gels again. After that it cracks on drying and the glaze crawls on firing. Is this really worth it? Actually, this recipe is fixable, the material at fault can be substituted (using a little glaze chemistry) to produce a much easier-to-use slurry.
Trafficking in Glaze Recipes
The trade is glaze recipes has spawned generations of potters going up blind alleys trying recipes that don't work and living with ones that are much more trouble than they are worth. It is time to leave this behind and take control.