well I just cleaned my CPR BalPak yesterday as a matter of fact and I couldn't believe all the gunk that was in there. I wondered why my nitrates were high and after I cleaned it out they dropped 40ppm It hadn't been cleaned in 2 months so I plan on cleaning it a t least once a month. My skimmer has bio filtration too and I rinsed the biobale in fresh saltwater and the water turned brown. One more lesson learned the hard way.
lol... that's a long time! i have the cpr bak-pak also... it's been a month, maybe i should disect it and give it a good cleaning... thanks for the advice everyone!