G4 pond sealer is applied to concrete ponds to prevent water from penetrating the concrete. Additionally it prevents toxic substances such as lime leaching into the pond. G4 pond sealer is polyurethane base, and can be applied directly to concrete, bricks and porous stone. 

Ensure that the surface is dust free and dry. It cures within 6 hours. Full mechanical hardness is achieved after 24 hours and chemical resistance after 72hours. It may be applied at temperatures from 00C. Normally 3 layers is applied for a durable seal. Coverage is approx 550gm per sq.m for the 3 applications.