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Re: Some good tips on keeping goldfish

Subject: Re: Some good tips on keeping goldfish
by Goldy on 28/7/2008 18:39:37

As the others have stated depends on the brand, I use Rena bio-chem zorb in my tank and this states 2-3 months

where as the API one states 3-6 months, see link below

http://www.petsparade.co.uk/aquarium/filter-media/?p=4529