I just siliconed the whole tank, and hopefully it will work. I used close to 2 tubes and laid it on thick which I am hoping will make it last. The tube says it should be good tomorrow however with the thickness I laid on I think I'm going to wait a couple just to be sure. It doesn't look as nice as it did when it was done by the factory however i will be covered by sand so it won't show. the corners look good though and that is what people will see. I will probably fill it up on Sunday and post what happens.