I have used Grapefruit-Seed-Extract but in rotation with nystatin, caprylic acid etc. I believe the Grapefruit-Seed-Extract helped and it was something I could use long term but it is hard to be certain with so many other antifungals at the same time.
They say though if you have caprylic acid and see if you get any reactions it is a good way to identify if you still have a problem. Could be worth trying. I have read though that caprylic acid can kill the good little bacteria so take some of that at the same time.
As for apple cider vinegar in all the books I have read they dont recommend it for someone with candida as it is fermented. I have never tried it as a cure so not sure.