I’ve noticed in most kits they include potassium metabisulphite, potassium sorbate, kieselsol and chitosan. Some even include yeast nutrients to be added when SG drops to 1.050-1.040. Are all these chemicals necessary? When I purchased a fresh pail of juice at a local shop, I questioned the owner if I needed to purchase the above ingredients and he said probably not. His only recommendation was to add metabisulphite at 6-8 weeks in secondary. So I’m a bit confused with the conflicting advice. I did notice when reading the directions included with the kits, they really hold your hand to an extreme. Almost to the point of second guessing yourself. Anyone care to chime in?