Changing sump styles: What to do with bio balls?

[gvillenative]

Hello everyone! I am changing my sump from the drip tray with blue balls without baffles to a filter sock and baffles to save room and be able to keep my skimmer in a sustained volume of water. I'm also adding an external refugium. What do I need to do with the blue balls? I've heard I need to take them out of the system slowly.

 

[nuwave59]

IMO, you should remove them slowy to give time to your new filter to build bacteria.