Hi There…. have you contacted the store where you bought it from…. are you also sure that the tap has been tightened correctly and are you sure that the collection of water over night is not condensation on the outside of the reservoir, this occurs when cold water is added to the tank in a warm environment. If you do discover there is damage they are under warranty as long as it is a manufacturing issue if the damage has been caused the warranty will not apply, you will need to provide your receipt….. please contact the retailer and I’m sure they will assist….. alternatively look at trying a bicycle tyre repair kit