That does not begin to address my questions
I do not want to stop using the cartridges. I am a long time aquarium hobbyist and well versed on adding my own filter material. However this is only for a 10
gal planted cycled tank and it serves my purpose very well. .
Also, the Aqueon filters have much surface area on the two blue holders where much good bacteria can also colonize.
In fact whenever you replace any filter media in any filter with anything, are you not also removing some goo\d bacteria?
BTW, I have a sponge pre filter on the intake that collects a surprising amount of crap extending the life of the cartridge. The sponge can be rinsed and reused many times of course

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