I took 1/8 -1/4 of a level teaspoon (borax) daily for a full year before I went over to maintenance dosage like 1-3 times a week. Candida gone, or at least under control:) No, candida / fungus do not get resistant to boron; they have no utilization for it.
You may need more than the 4 capsules (12 mg?) to combat candida.
Borax filled in empty capsules, with vit C and magnesium; works for me!