Help me avoid Crisis!

[jaylin]

Only in extremely unusual conditions not generally found in aquaria. I advise leaving it in; it will be colonised with bacteria now and you don't need carbon, so the "full" carbon might as well be left in there as bacterial media.

That's not true - once that carbon gets filled up you see equilibrium rxn's starting to happen. Whereby some gunk is swapped out for other gunk in an attempt to maintain levels of equilibrium between what's in the carbon and what's in the water.

And the girl has biowheels - why the heck does she need the bacteria on her carbon?? She's already said the filters are so clogged that they're starting to back up. Why do you want to set her up for a fish spill on the carpet?