Dipping live rock

[don.ald]

Originally Posted by Aquattro

Rock that is old, especially from a low flow area such as a sump, IMO will be full of crud (PO4). I just removed 3 yo rock from my tank from a high flow area and it was full of crap.
Also, I have to question why the addition of rock is warranted? What purpose does it serve, other than trapping detritus in the sump? Was additional denitrification needed? How was this determined?
Simply adding more rock for the sake of adding more rock seems pointless. More is not better.

So, when you remove rock from your system do you cook it and replace or do you purchase new "fresh" rock to replace?