Aqueon Aquarium Silicone Sealant, Clear, 10.3-oz Tube Keep your aquarium leak-proof with the Aqueon Aquarium Silicone Sealant. Formulated with 100% silicone, it forms a clear waterproof seal to stop leaks, and does not crack or shrink when applied. It?s actually the same high-strength silicone that?s used to make new aquariums so it?s a long-lasting, professional-grade bond you can trust. And since it?s non-toxic, it won?t harm plants or fish and works in both freshwater and marine aquariums. Plus, the formula is proudly made in the USA. (description exceeds maximum possible length)