Hedday Aquarium Filter Cartridges, 12-Pack Blue with Cotton Media and Activated Carbon

Hedday filter cartridges are a 12-pack of blue replacement cartridges for compatible aquarium power filters, with cotton media and activated carbon for routine aquarium filtration.

• 12 blue cartridges — keeps replacement cartridges on hand for regular aquarium maintenance.
• Cotton media and activated carbon — combines debris capture with an additional filtration layer.
• Tool-free replacement — slide a new cartridge into the filter slot after removing the old one.
• Replace every 2–4 weeks or as needed — adjust replacement to aquarium conditions and filter performance.

These cartridges are made for routine care of aquariums using compatible power filters. Their cotton media helps capture visible debris and fish waste, while activated carbon adds another filtration layer. The 12-cartridge supply supports ongoing replacements, with timing guided by the conditions in your aquarium and how your filter is performing.

Which aquarium filters are these cartridges compatible with?

Hedday filter cartridges fit Aqua-Tech 20-40 and 30-60 power filters that use EZ-Change #3 cartridges, as well as Marineland Penguin PRO 275/375 and Penguin 200/350 power filters that use Rite-Size C cartridges. They are compatible replacement cartridges, not original Aqua-Tech or Marineland parts. Before choosing, confirm your filter model and cartridge size, then compare the width, height, and thickness of your current cartridge.

• Aqua-Tech format: EZ-Change #3.
• Marineland format: Rite-Size C.
• Check all three cartridge dimensions against your current cartridge before purchase.

What do the cotton media and activated carbon do?

The cotton media helps collect visible aquarium debris and fish waste, and the activated carbon provides an additional filtration layer for regular aquarium care. Together, these materials make the cartridges a replacement option for routine use in the compatible filters.

• Designed for routine aquarium filtration.
• Use the cartridge format that matches your power filter.

How do I replace a cartridge?

Rinse a new Hedday filter cartridge with cool water before using it, remove the old cartridge, and slide the replacement into the filter slot. No tools are needed. Replace cartridges every 2–4 weeks or sooner or later as needed based on aquarium conditions and filter performance.

• Rinse with cool water before first use.
• Remove the old cartridge before sliding in the replacement.
• Replacement timing depends on aquarium conditions and filter performance.

Hedday filter cartridges suit aquarium owners maintaining Aqua-Tech or Marineland power filters that use the compatible cartridge formats. They are intended as replacement cartridges for the specified filters, rather than original-brand parts, and the format and dimensions should match your current cartridge. Each pack contains 12 blue cartridges with cotton media and activated carbon for ongoing routine care.

Ingredients

cotton and activated carbon

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