How to Remove Mildew From a Watercolor Painting
- 1). Remove the painting from the damp environment it is in, and place it in a dry area. Keep the painting out of direct sunlight. If the paper is damp, allow it to dry thoroughly before proceeding.
- 2). Spray a thin mist of antibacterial spray onto the painting, front and back. Let the painting dry for several days.
- 3). Inspect the painting. If the antibacterial spray has killed the mildew, it will have turned into a dry powder.
- 4). Take the painting outside, and carefully brush off the dried mildew with a soft brush.
- 5). If mildew still remains, repeat the application of spray and brushing.
Source...