Regarding the use of Stabilized Vitamin C (Natural-C Glycol™) Serum

Based on the information for Stabilized Vitamin C (Natural-C Glycol™) Serum, this product is formulated as a finished serum ready for use. The manufacturer advises that it is not suitable for mixing with any additional ingredients as this may affect its stability and effectiveness.

Therefore, adding this Vitamin C serum into your current multi-step routine alongside Job's Tears lotion, Turmeric extract, Vitamin B3 serum, Collagen Drops, sunscreen, and powder is not recommended due to the potential for negative interactions and compromised stability of the Vitamin C.

As the staff reply suggested, if your current routine is working well, it's best to continue with it. If you wish to incorporate this Vitamin C serum, it would be more appropriate to use it as a standalone treatment, perhaps on alternate days or nights when you are not using your full routine, or potentially using it to replace one of your existing serum steps (like the Vitamin B3 serum or Collagen Drops) if you feel those are not providing the desired results.

Regarding application time, the staff's advice is sound: it can typically be applied morning and/or night, depending on your skin type (less frequent for oily skin, potentially morning and night for normal to dry skin). However, always apply it to clean skin and allow it to absorb fully before considering any other products, keeping in mind the strong recommendation against mixing.

In summary, due to the specific formulation of this Vitamin C serum, it is best used separately rather than layered within your extensive current routine.