Dear Mrs. Mark,
We were distressed to learn that a faulty connection had resulted in a leakage in your water filtration system and are happy we could adjust this before there was any damage to your facilities. Even though you have had the equipment for six years, there should be no problems of this nature.
When our design engineer inspected the piping circuit, he noted that your use of water has almost doubled since the initial installation. He strongly suggests that you let us add one more holding tank and sub-filter to accommodate this increased flow.
Because you are a valued customer, we can give you a 20% discount on the upgrading cost.