I have a remodeling company in a rural area in the midwest where good plumbers are hard to come by. I have a good customer who has developed a problem with his water system.The system is a well which receives its water from a pond, the problem is in one bathroom the water from the tub faucet comes at black for ten to fifteen seconds when first turned on. This is the only fixture in the house that has this problem. The water lines are all copper probably thirty years old. The plumbers have changed the faucet and the spout along with a few steel fittings they found and now they say they have know idea whats wrong. The water also seems to have a odor when first turned on. As i said these have been good custermers and now they have turned to me for a answer and our local plumbers are know help now so any advice would be greatly appreciated. thanks in advance.