AK Interactive Terrains: Water Gel Swamp GreenBrown Green dense gel for swamp waters. To create a sense of depth, apply the gel over a painted surface. Drying time is dependent on the amount used; however, 24 hours is what we recommend. This is a high quality acrylic product developed for extreme realism. Acrylic product for textures in dioramas. Perfect results in layers from 0. 1 to 3 mm. It can be diluted with water or an acrylic thinner to improve its flow. No toxic