Activated carbon lifespan

Hi folks,

I use activated carbon in a power filter for my aquarium. I probably
don't really need it since I do 20% water changes each week anyway, but
I like to have the water as free of impurities as possible and it does
seem to make it smell cleaner :-) I'm interested in knowing how to tell
exactly when a batch of activated carbon has absorbed as much organic
waste as it can hold and has reached the end of it's lifespan. I
regularly change it every month, but I don't like having to guess as the
stuff is probably still good and I'm wasting money and effort and
throwing away whatever beneficial bacteria has gathered on the granules.

I'd also like to know if it can be easily cleaned and recharged. I read
in a few places that the absorbed waste material can be separated from
the carbon by baking it at a high temperature but I can't find the
details of the process. Can it be done in my oven at home? Also, is it
possible that by tapping and breaking the carbon granules with a mallet
you can expose fresh unused areas of the carbon and extend it's life
that way?

Thanks for any tips!

- Logic316


"Bureaucracy: The process of turning energy into solid waste."