I'm a new soaper. First batch, CP, I used my own rendered tallow and tap water. As the bars cured, they continued to develop brown spots. Watching Youtube, I heard that lye can react with tap water and one should use distilled water. So batch #1 goes in trash.
Second batch, Hot processed, no animal fat and distilled water. Although on a smaller scale, I am still developing brown spots on my soap. What the?