Seal-Once makes a product that has zero VOCs, is eco-friendly, nontoxic and safe to use with pets/plants/fish.
It provides mold and mildew protection and is safe for use over water. It is water-based, non-flammable and provides long-lasting protection against water and UV damage. You can choose from clear or tinted formulas, and it is suitable for all climates.
The product is NHDES approved and is listed by GreenSpec. It claims to protect vertical surfaces for 10 years and horizontal surfaces for 6 years.
To investigate this product you can go to Seal-Once.com.
For more information:
Read Matthew Bremer's Q&A "Can you recommend a nontoxic waterproof wood sealer for my outdoor window boxes?"
Read our clear finish buyer's guide for detailed comparison of finishes.