• 1 cup washing soda or Na2CO3 or sodium carbonate
• 1 cup baking soda
• 1 cup salt
• 3 tablespoons lemon juice
• 1 cup water
1. Mix all the above ingredients, and pour a shallow amount into an ice cube tray (if you don’t have any, you can usually find them at the dollar store).
2. Leave them to dry for 24 hours, or until the liquid has been absorbed. These tablets won’t shrink as they dry, so whatever size you pour, is the size that they will remain.
3. Once dry, pop the tablets out of the tray, and store in an airtight container.