ok,to alleviate the confusion and save lots of money.
1) There's no need to change the filters every month,manafacturers get more money and there's no need.
2)The filters only need to be washed off to get rid of gunk build up
3) can be re-used until they fall apart
4) carbon removes
ammonia from the water (acts like a magnet and adsorbs it from the water) ammonia is needed by the bacteria for the bio-filter (
nitrogen cycle)
You can use carbon or not,that's specifically a personal choice. I DO NOT use carbon except in quarantine to remove meds.
Instead of using the manufacturers filters use these:
http://www.3m.com/us/home_leisure/sc..._scouring.html
WITHOUT cleansers,soaps,chemicals...........Don't worry,the package says "not for aquarium use" but are safe as long as THERE ARE NO CLEANSERS,and last FOREVER (literally)
The ones I am referring to are the blue or green pads in the middle of the advertisement,they come in an open package (not plastic wrapped,the ones in plastic contain chemicals,soaps and detergents)
You can buy them anywhere for $2 and can be cut down to any size with a pair of scissors.They are thin and sometimes you need 3 or 4 to fill the gap the normal cartridges use. I stuff 8 or 9 in the hole,and pull 1 or 2 out to seed a new aquarium (almost instantly cycling ANY aquarium).
I have these stuffed in my
DIY canister filters as well.The best filter media you can buy.You can also use these.
http://images.google.com/imgres?imgu...%3Den%26sa%3DN
I use a combination of the scotch pads and nylon scrubbers,they work excellent and never need to be replaced.