Formula Review and Suggestions

Your proposed serum formula is generally compatible, with no major ingredient conflicts. The ingredients included are suitable for a water-based serum.

Based on your goal of creating a serum texture, the concentration of Glycerin Gel at 3% is likely too low. As noted in the previous discussion, a starting point of 10% or higher is typically recommended for Glycerin Gel to achieve a noticeable gel texture. At 3%, your formula will likely be quite liquid, more like a toner or essence than a serum.

The inclusion of Disodium EDTA at 0.2% is appropriate for chelating metal ions in the water and improving formula stability.

You have included Phenoxyethanol plus (assuming this refers to Phenoxyethanol SA eq. Optiphen Plus) at 0.8%. This is within the recommended usage range and provides broad-spectrum preservation for the formula, which is necessary given the high water content and the inclusion of Galactomyces Ferment Filtrate (Pitera).

Galactomyces Ferment Filtrate (Pitera) is included at 55%. This is a high concentration, which is good for efficacy. While Pitera itself may contain a preservative (like Butylene Glycol in the standard version), your inclusion of an additional broad-spectrum preservative like Phenoxyethanol plus is appropriate, especially since the Pitera concentration is below the 60% threshold where a preservative might become optional.

Suggestions:

• To achieve a serum texture, consider increasing the concentration of Glycerin Gel. Start with 10% and adjust based on your desired viscosity.
• The current ingredients provide basic hydration and the benefits of Pitera. Depending on your desired skin benefits, you could consider adding other water-soluble active ingredients such as Hyaluronic Acid for enhanced hydration, Niacinamide for various benefits, or other botanical extracts.

Overall, the formula is safe and compatible, but adjust the Glycerin Gel percentage to get the desired serum texture.