It's not something you want to spend money on, but you really need to pump your tank annually. We have used WindRiver since 1998 and they do a good job. They are always polite, professional and show up on time.
The tech we have had for the past few years is Jim, and he does a good job explaining why the system performs (or does not perform).
I skipped using their CCLS additive for one year, and it was a mistake. Fortunately I scheduled service just before the tank got in really bad shape. Now, I definitely use the additive and it made a difference.
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