I use pond hose. Black, comes reinforced, and seals to corresponding hose barbs perfectly. It bends better than PVC flex and as we aren't using it for pressure applications... (5 psi tops)... it will work fine. Cheap too. I thought I would have to maybe replace it somewhat regularly as I thought it may stiffen and get brittle... but 2 years running in various appilcations and not one problem, and the hose seems as pliable as day one...(touches wood). :smile: Just my 2 bits...