ASI Aquarium Silicone Sealant has been specifically formulated for the fabrication of fresh and salt-water aquariums. This high modulus component RTV Silicone Sealant forms strong cohesive bonds to glass without the need of primers. The bonds are unaffected by continuous immersion in water and, when fully cured, is non-toxic to fish. ASI silicone for aquarium Sealant is a non-slump sealant and can be applied to vertical surfaces without flowing or sagging.