Well this would be my $.05, I would eliminate any and all galvanized fittings along with that relic tank (Would make a great lawn roller). I have a "public water system' at our cottage rental business and by eliminating all the galvanized fittings, tank, etc. the water quality is absolutely fantastic. both in taste and clarity. All fittings are either brass, copper, stainless or plastic. We do have to chlorinate due to state guidelines, but after setting up municipal systems, I only use sodium hypochlorite. As for the control tank, get a bladder lined unit of appropriate size for your use. If you have any turbibity, get one of the large whole house filter assemblies. Hope this was not too long and maybe a little helpful.