Analysis of Your Serum Formula

Based on the formula you provided (Witch Hazel 85%, Azelaic Acid 10%, Sea Kelp Bioferment 5%), this combination can indeed be used as a night serum and is formulated to address your goals of skin brightening and pore tightening.

Here's a breakdown of how the ingredients work:

• Witch Hazel (85%): Witch Hazel is well-known for its astringent properties, meaning it helps to tighten pores and reduce excess oiliness. Using it at a high concentration like 85% can be very effective for pore tightening. The types of Witch Hazel available are alcohol-free distillates, which are less irritating than traditional versions.
• Azelaic Acid (10%): The Azelaic Acid product you likely refer to is a water-soluble form (Potassium azeloyl diglycinate), which is effective for skin brightening, reducing dark spots, and controlling oil production, which indirectly helps with pore appearance. A 10% concentration is at the higher end of the recommended usage rate for significant brightening and oil control effects. Due to its exfoliating properties, using this serum at night is recommended to avoid sun sensitivity.
• Sea Kelp Bioferment (5%): Sea Kelp Extract provides moisturizing and nourishing benefits. It helps maintain skin balance, strengthens the skin barrier, and offers antioxidant properties. While the recommended usage rate for skin is typically 1-3%, 5% is within the acceptable range and adds hydration and overall skin health support to the formula. Be aware that using it at this concentration might introduce a slight marine/fishy smell.

Overall:
This formula is potent, particularly with the high concentrations of Witch Hazel and Azelaic Acid. It is suitable for night use and targets skin brightening and pore tightening effectively. The Sea Kelp Bioferment adds hydration and soothing properties to balance the potentially drying or exfoliating effects of the other two ingredients.