Browse Forums Pools & Spas 18 90358 From what I know about water tanks (I've been working with a client on them for a few years now) is this - The concrete can last a lifetime if they don't crack for some… 2 10516 If you can calculate the reasonable charged head from let's say 100mm below the gutter to the top of where the vertical riser's horizontal discharge pipe will be, that… 11 17513 |