Water Poof Acetoxy Silicone Sealant is non-fungicide and is not harmful to marine life. The Acetoxy Silicone Sealant is suitable for heavy-duty marine work; building and repairing fish tanks and large-scale aquariums. The Acetoxy Silicone Sealant can also be used for jointing and sealing for glass. Water Poof Acetoxy Silicone Sealant is permanently flexible and resists cracking or shrinking.