I have to admit that I don't know why I used something else. For the price of activated charcoal alone, it comes with a built-in pre-filter. I just cut it out to fit the hanging filter I use for my aquarium and it does a great job of replacing those expensive cartridges that I never liked. I've found polishing filters that I can add, but I don't really see the need for it.
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KEDSUM Battery Aquarium Air Pump: Ultra-Quiet Rechargeable Fish Aerator with Dual Outlets - Ideal for Fish Tanks, Outdoor Fishing, Fish Transportation, and Power Outages
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Humidifier / air purifier "Fanline Aqua VE400" with an ionizer, with a capacity of 410 gr/h
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Powerful And Quiet Submersible Pump For Aquarium, Pond, And Hydroponics: KEDSUM 660GPH Pump With 6Ft High Lift And 3 Nozzles
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Vacuum cleaner TEQQO Aquastick 3 in 1 Power, grey/turquoise
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Mini pump Xiaomi Mijia Electric Pump 1S, plastic, black
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Efficient 2-In-1 Magnetic Fish Tank Cleaner With Non-Slip Design And Scratch-Free Blades
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π U-BCOO Aquarium Gravel Cleaner Fish Tank: Manual Siphon for Efficient Filter Gravel Cleaning and Water Change in Tanks
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