Mosquito Repellent Spray Formulation Adjustment

You have a water-based mosquito repellent spray formula using diluted wood vinegar, citronella essential oil, and Flora Solve™ Clear. You've found the pH is 3.8, which is quite acidic.

Adjusting pH

To increase the pH of your formulation, you can use Sodium Hydroxide solution. It's a common ingredient used to raise the pH in cosmetic products.

• How to use: Prepare a dilute solution of Sodium Hydroxide in water (e.g., 1-5%). Add this dilute solution drop by drop to your mosquito spray mixture while stirring constantly. Measure the pH after each addition until you reach your desired pH level. For skin application, a pH closer to the skin's natural pH (around 5.5) or slightly higher might be more suitable, but given the wood vinegar component, a pH in the range of 4.5-5.5 could be a reasonable target. Always add the Sodium Hydroxide solution to the formula, not the other way around.
• Usage Rate: The typical usage rate for Sodium Hydroxide is 0.1-5%, but you will likely need much less than 0.1% of the pure Sodium Hydroxide to adjust the pH of your existing formula. The exact amount needed will depend on the concentration of your Sodium Hydroxide solution and the acidity of your wood vinegar dilution. It's crucial to add it gradually and test the pH frequently.

Adding Euca-Kill™

Euca-Kill™ is an effective insect repellent ingredient. However, based on its properties, it is primarily soluble in Glycol, Alcohol, or oil, not directly in water. Since your formula is 99% water-based (diluted wood vinegar), adding Euca-Kill™ directly might not fully dissolve or could cause the mixture to become cloudy or separate.

• How to incorporate: To add Euca-Kill™ to a water-based formula, you would typically need to dissolve it first in a suitable solvent like alcohol (e.g., Ethanol) or a glycol (e.g., Dipropylene Glycol) before mixing it into the main water phase. This would change your formula significantly from a simple water-based spray.
• Usage Rate: If you choose to reformulate to include Euca-Kill™, the recommended usage rate for insect protection is typically 12-15% for 2-3 hours of protection or 25-30% for 5-6 hours of protection.

Given your current formula is primarily wood vinegar and water, incorporating Euca-Kill™ effectively would require a different approach, likely involving a co-solvent, which would change the nature of your spray from a purely water-based system.