# How often should I change my filter cartridge?



## aquyenl (Jan 12, 2010)

I've heard some mixed responses on how often it is needed to change filter cartridges. I use a marineland 12 filter with the biowheel and the instructions say to replace the filter cartridge with a new one every 2-4 weeks. However, after reading some of the other threads about filter media, I have heard that you are to keep the filter cartridge that you have as long as possible and just dunk it in water that is to be thrown out during partial water changes. This would seem to make sense as you get to keep a lot of the beneficial bacteria that has grown on the cartridge. Can anyone clear up what you are supposed to do with filter cartridges? Thanks!


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## aspects (Feb 1, 2009)

change the filter cartridge according to manufacturer instructions on the package.
those filter cartridges are filled with carbon which is only "active" of 5-7 days, at which point its useless. i would not keep them for longer than 2 weeks. 

some people advocate the "rinse and reuse" method,. but these cartridges simply aren't built for this purpose. they are made of a thin layer of filter floss wrapped around a small plastic frame. each time you wash it, you damage the fibers and disrupt the structural integrity of the floss. this will lead to the floss getting clogged faster, or even opening holes in some areas.

your best bet is to just replace the filter with a proper mech/bio filter if youre able to do so .


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## emc7 (Jul 23, 2005)

I'm cheap, I keep them as long as I can and even replace them with 3rd party no-name replacement cartridges (Ken's fish has some). Manufacturers seem to be catching on to people like me and the cartridges are starting to fall apart sooner and sooner. Aspects is right that the charcoal is soon useless as anything but a surface for biology to live on. But chemical filtration isn't a priority for me. Certainly chucking all your media half-way through cycling because the directions say to is kind of stupid.


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## Sea-Agg2009 (Aug 2, 2008)

Carbon is really only used for removing chemicals, like chlorines and heavy metals, from your water. Aside from the initial cycling and water changes, there really shouldn't be any additional chemical loads unless you are spraying household cleaners into your tank. I generally rinse mine out before I do a small water change, and replace mine ever 2-3 months. 

If you don't have plants in your tank, the biological filtration is a much more important aspect (removing ammonias and nitrates). Allowing the carbon to "mature", allows ammonia reducing bacteria to grow on your filter. Over-cleaning your filter will disturb those communities. If you are simply concerned about the nitrates and such, then only rinse your filter to get the "muck" off it, and with room temp water.


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