I now have a new Grundfos Sololift2 WC-1 still in box. It looks like Since this is a swap out it looks like I need an additional Grundfos accessory in the form of a flexible pipe. The waste pipe installed is 22mm and the Grundfos was exit elbow 32mm (internal). Could I get some suitable reducers and flexible pipe from a plumbing supplies/DIY store or do I need to get the official accessory from Grundfos? I would need some hard plastic or nylon reducers (22-32 mm) to use with hose clamps?