If you intend to use nystatin, use it alone and not along with oregano oil, GFE & Peau d'arco. These are all antifungals, use one at a time and rotate them every three weeks or else use nystatin and mo need to rotate.
As per quantity and storage I have no clue, my chemical antifungals do not need any specific storage.
olive leave, friendly bacteria acidophilus and green food with antoxidants are a great combo. Also supplement in chloride magnesium (liquid form assimilates better) or else any magnesium supplement.