From our experience, cratering or fish eyeing almost certainly indicate that one of three things occurred during your application:
1. Insufficient drying and/or incompatibility with a stain or oil: Pre-testing is always recommended when using products from another manufacturer.
2. Sanding too smooth can cause the epoxy to draw away from the surface. For example, sanding higher than 220 grit will make it difficult for the Mirror Coat to overcome the surface tension of the substrate.
3. Lack of coverage: We specify pouring the MirrorCoat at 4 oz/sq ft to allow enough coverage on the substrate. Any less will result in a lack of adequate coverage.