PVC piping is usually used outside of the pond and is a hard white pipe. In order to turn the direction of the piping there are plumbing fittings that will be needed to be used. PVC comes in straight pipe and will need to be cut and glued with PVC Cement. PVC can be purchased at a local hardware store and will last a long time but does not give you the flexibility that other hoses have. Flexible PVC Hose is black in color and will give you a little bit more flexibility then its PVC straight pipe as it can curve. The less diameter the easier it is to make a curve. It is smooth on the outside and inside. It also uses the same PVC fittings and cements as the schedule 40 white pipes to make connections. It’s very durable and is usually used outside of the pond.