With soaping there is never one size fits all.Regarding soda ash, quoting from The Soap Maker's Planner by Jackie Ziegler, a longstanding and respected New Zea;and soaper: "... Soda ash occurs when the lye molecules react with the carbon dioxide in the air to form soda bicarbonate. It is completely harmless, but can ruin a design, eg a mica swirl on top. Do NOT spray alcohol on the surface of the soap. This will NOT get rid of or prevent soda ash. Instead, by spraying alcohol, you are actually cleaning the surface, allowing more air to reach the surface of the soap, and thus you are worsening the problem. To prevent soda ash, you can either limit air contact or reduce the amount of free lye molecules in the soap. To limit air contact, you can cover the soap with baking paper or wax paper. To reduce the amount of lye molecules in the soap, you need to complete as much of the saponification process as possible. You can either do a hot process (hot process never has soda ash), heat at higher temperatures, or ensure you stick blend long enough to reach a thicker trace. Cooler and more fluid soaps tend to have more soda ash."
I see that others answered this. My answer was location and how other soap play a factor in soda ash forming. Water Discount can help but you'd have to feel comfortable doing that and your recipe should be pretty familiar to you before attempting that change.Why do so many people say to spray with alcohol to prevent soda ash? I must have read this hundreds of times if not more???