Thanks for all the feedback. I guess i could have saved about $100 over the last 4 years of changing the carbon/zeolite filter bag... One part of me does not want to change what I have been doing for years as I've always had very healthy tanks ( never any disease outbreaks or algae blooms ) but I'm also not against change and fine tuning. So I'm thinking then to go with 2 sponges and leave the ZeoCarb bag on the top but just never wash it out so that it holds the bacteria.
Funny, I was always under the impression that the chemical part of hte filter system was more important, and actually felt alittle guilt when I had not changed the chemical component on a monthly basis.
