Our 32 x 13 inground gunite kidney pool was probably built in 1977. Now we have water splashing out the backside of the berm behind our pool whenever we use our robot vacuum. Pretty good guess there is a discontinuity in the plumbing somewhere near that point. We have been warned about possible overcharging and other problems with the local pool plumbing repair companies. Is it reasonable to think that I could get a diamond circular saw blade and cut a 3' x 3' wall section out around the fitting and reach behind the wall and repair the problem? Associated with this is how to replace the sawn section? Is it likely that all the plumbing is aged out and should be replaced? There is another suspicious place behind an inlet where the bushes behind the pool are dying, possibly because of chlorine poisoning. If all plumbing should be replaced how is this done? The deck/apron is Sundeck.