Here is the review of your proposed toner formula, quantities, and mixing method based on your questions and the previous discussion:

Toner Formula Review

1. Is the formula okay?
Yes, the formula looks very good. It contains a powerful blend of ingredients specifically chosen to address your concerns:

• Hydration & Barrier Support: Panthenol, Glucosamine, Natural Moisturizing Amino Acids, Hyaluronic Acids, Allantoin. These help combat dehydration and strengthen the skin barrier, which is crucial for oily but dehydrated skin.
• Soothing & Anti-inflammatory: Panthenol, Niacinamide, Green Tea Extract, Allantoin, Centella Asiatica Extract, Glucosamine. These ingredients help calm inflammation associated with acne and irritation.
• Improving Skin Tone & Marks: Niacinamide, Glucosamine, Centella Asiatica Extract, Green Tea Extract. These can help reduce the appearance of red and dark marks left by acne.

The combination is synergistic and well-suited for your skin type and concerns.

2. If the ingredients are okay, are the quantities correct?
The quantities you've selected result in a highly concentrated toner with approximately 30% active ingredients (excluding water and preservative). These concentrations are generally within effective and safe ranges for cosmetic use and should provide significant benefits. The total quantity is close to 100g, which is a standard batch size. The final product will likely have a slightly viscous texture due to the high active load and hyaluronic acid.

3. Is the mixing method correct?
No, the proposed mixing method needs a slight adjustment based on the previous staff advice regarding hyaluronic acid. Adding liquid ingredients before the hyaluronic acid can hinder its ability to hydrate and form a gel properly.

Corrected Mixing Method:

1. Measure the water (70 ml/g) into a clean container.
2. Add the powder ingredients that dissolve easily: Vitamin B3 (Niacinamide, 5g), Glucosamine (N-acetyl-D, 5g), and Allantoin (0.35g). Stir or shake until they are fully dissolved.
3. Add the hyaluronic acid powders: Hyaluronic Acid (Standard Molecule, 0.5g) and Hyaluronic Acid (Nano Molecule, 0.5g). Stir briefly to disperse, then let the mixture sit undisturbed for several hours (or overnight) to allow the hyaluronic acid to fully hydrate and form a gel. Shaking periodically and refrigeration can help speed this up.
4. Once the hyaluronic acid is completely dissolved and the mixture is a uniform gel, add the liquid ingredients: Panthenol (Pro Vitamin B5, 5g - assuming liquid form), Centella Asiatica (Gotu Kola) Extract (5g), Natural Moisturizing Amino Acids (5g), Green Tea Extract (2g), and Phenoxyethanol (1g). Stir or shake gently until everything is evenly mixed.

Ensure all ingredients are fully dissolved and the mixture is uniform before bottling.

Including Phenoxyethanol at 1% provides necessary preservation for the toner. While it should be stable for travel, storing it in a cool, dark place or refrigerating it when possible will help maintain its quality and shelf life, especially given the natural extracts.