[Canadian Man]

Originally Posted by UnderWorldAquatics

I use pool and spa fexible PVC, its white, smooth inside and out, has internal ribing so it cant collapse, you can usually pick it up at any pool or spay wholesaler or retailer...

me too but for my return I use pond tubing. It's smooth on the inside and flexible. It has a skeleton on the outside in a coil pattern. Oh and it's black.