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Amazon.com : AST Bubble Bead Filter XS1000, The Original Bead Filter, Pond Filtration Solution, Perfect for Koi Ponds Up to 1000 Gallons, Pond Media Included, Media Lasts Forever : Pet Supplies
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Amazon.com : AST Bubble Bead Filter XS2000, The Original Bead Filter, Pond Filtration Solution, Perfect for Koi Ponds Up to 2000 Gallons, Pond Media Included, Media Lasts Forever : Pet Supplies
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