This clever sealer will allow you to repair cracks/holes etc or bond items to your pond/aquarium/tank underwater and is safe for fish! Being non-toxic, solvent and isocyanate free there is no need to drain your pond or disturb your fish any more in order to make a repair! With the strength of 4 times a normal silicone sealer it will bond almost anything to anything including drains, gutters, tanks, boats, rockery, coral, decking, concrete (please note, if applying to concrete, a PVA or concrete primer will be needed prior to application to seal any loose surfaces), wood, PVC, glass etc. It will start to work instantly and will continue to cure over 24 hours. Available in Black, Clear & White in 290ml cartridges and Black & Clear in our “One Shot” version. Please note; cure times vary between colours and the amount applied.