Seachem Silicone Sealant 

Seachem Silicone Sealant is a room-temperature-vulcanising (RTV) silicone rubber and is made specifically for sealing and repairing aquariums. It remains permanently flexible, has a high tensile strength and is stress resistant. It can be used in both fresh and salt water and provides a reliable watertight seal. Furthermore, it is completely harmless to all aquarium inhabitants and aquatic plants.

• 100% RTV silicone rubber for aquarium use in black or clean
• Does not shrink or crack
• Resists pressure and stress
• Reliable watertight seal
• Suitable for use in freshwater and saltwater tanks