Filter media question?

Question
I have a Fluval FX5 and I have pad filters in one tray, biomax in one, and charcoal bags in the last one. Now I saw that I replace the pads weekly, but there is no info on when to change charcoal or the biomax. How often should they be replaced? I read some sites say every 6 months for biomax and some say never just rinse it. As for charcoal I can't find any info anywhere.

Answer
Hi Dustin,
  The manufacturers would ideally like you to change stuff all the time.  In reality, I almost never change the foam ones, I just rinse them.  The charcoal is of dubious value even when it is new.  I never use charcoal.

-- Ron C.
  rcoleman@cichlidresearch.com
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