Does live rock have a life span?

[michika]

I can tell you from first hand experience there is an "expiry" date on your rock and I definitely noticed it when my system hit is threshold for nutrient export. Granted at the time it was really difficult to see and pinpoint, but in hindsight and after having made numerous unsuccessful changes before swapping out my rock.

I plan to rotate pieces in and out of my new tank to try and address this long term, plus teaming this up with aggressive alternative nutrient exporters, skimmer, media, filter socks, etc.