Introducing the Xiaomi (Mijia) Smart Fish Tank Gen-2 Modular Filter Cartridge, designed specifically for the second generation of Xiaomi smart aquariums. This replaceable filter module enables easy customization and maintenance — perfect for fish-keeping enthusiasts who want to upgrade or service their tank’s filtration system.

This replacement filter pack provides a 6-layer composite filtration system, combining physical and biochemical media. With modular, detachable design, you can disassemble the filter housing, clean or replace individual filter materials, and maintain optimal water quality with minimal hassle.

🔍 Key Features

• Modular & Removable Design: The filter housing (filter box) can be opened to access internal filter media. According to user-shared teardown videos, you can pry open the housing and re-seal after cleaning or replacing media.

• 6-Layer Composite Filtration: Includes physical cotton filter (e.g. PP or 6D filter cotton) and multiple nitrifying (biological) modules.

• Long Maintenance Cycles: Well-designed filter structure helps maintain water quality, reducing the need for frequent water changes.

• Customizable Filter Media: After opening the housing, you can add or change filter materials as needed (e.g. stronger bio-media, activated carbon, ceramic rings), enabling performance upgrades.

• Easy to Clean: Users recommend rinsing filter cotton or other reusable media in old aquarium water (not tap water) to preserve beneficial bacteria

✅ Compatibility & Use Cases

• Designed for Xiaomi / Mijia Smart Aquarium Gen-2 (second generation).

• Ideal for users who want to maintain or upgrade their filtration system without replacing the entire filter block.

• Perfect for:

  • Improving water clarity

  • Boosting biological filtration (especially in more stocked tanks)

  • Reducing maintenance cost by reusing parts

  • Modifying filter media (DIY / custom media)

⚠️ Tips & Maintenance Advice

• When opening the filter housing for the first time, be careful: many users report that if you separate the module, the original seal may not be as tight afterward. 

• Use a flat-head screwdriver or similar tool to gently pry open the filter cover, then tap gently (some users use soft hammering) to separate.

• After replacing / cleaning the media, reseal the housing firmly to avoid leaks or reduced filter efficiency.

• For biological media (e.g., nitrifying cubes), rinse in tank water, not tap water, to protect beneficial bacteria. 

• Monitor water flow: if flow drops, it may be time to clean or replace the cotton or media.

Why Use This Modular Filter Replacement?

• Cost-effective: Rather than buying a whole new filter block, you can just replace the internal media.

• Customizable: Change the type of filter media (e.g. more bio media, or add chemical media) to suit your setup.

• Longer Filter Life: By cleaning the physical media and reusing some parts, your filter block lasts longer and maintains good performance.

• DIY Friendly: Hobbyists who like to tweak their setup will appreciate the modular, openable design.