For best results ensure that the surface is clean, dry and free of any dirt and grease, and clean with Gold Label Cleaning Solvent. Make sure that you cut a large enough angular hole in the nozzle to ensure that the beading you apply is thick enough, as this will ensure a stronger seal. We recommend a bead of about 5-10mm and to apply the sealer in a smooth continuous action, avoiding thin layers. For optimum structural strength apply the sealer across a right angle/corner joint, creating a triangular shape. (see image here). If constructing a tank or aquarium from scratch, ensure that the walls are being held securely before applying sealer. These will need to stay in place until the sealer has completely cured. This should take approximately 24-36 hours depending on thickness of beading. (Vulcanisation occurs at 1-2mm per 24 hours). Clean any excess off with Gold Label Cleaning Solvent. Please note: Keep away from children & avoid contact with eyes and skin. If contact with eyes occurs, rinse thoroughly with water & contact a doctor.