Chihiros External CO₂ Diffuser – Inline Atomizer (M & L Variants)

The Chihiros External CO₂ Diffuser is a high-efficiency inline atomizer designed to inject CO₂ directly into your canister filter outflow. By diffusing gas within the return hose, it maximises contact time and ensures superior CO₂ dissolution—resulting in stable levels and optimal plant growth without visible equipment inside the tank.

Key Features

Inline CO₂ Injection (Maximum Efficiency)
Installs directly onto your filter return hose, allowing CO₂ to mix thoroughly before entering the aquarium for improved absorption.

Ultra-Fine Ceramic Diffusion
Integrated ceramic disc breaks CO₂ into micro-bubbles, creating a fine mist that dissolves quickly and efficiently.

Cleaner, Equipment-Free Aquascape
External installation keeps your tank free of glass diffusers and clutter—ideal for display aquariums and aquascaping.

High CO₂ Efficiency & Stability
Longer contact time in the hose improves gas utilisation and helps maintain consistent CO₂ levels—even in demanding planted tanks.

Durable Acrylic & Ceramic Build
Constructed from high-quality acrylic with a replaceable ceramic diffusion plate for long-term reliability.

Silent Operation
Operates quietly within the filtration system, with no visible bubbles or noise inside the aquarium.

Variants Available

• M – 12/16mm Hose
  Ideal for small to medium aquariums and standard canister filters
• L – 16/22mm Hose
  Designed for larger tanks and higher flow filtration systems

(Always match the diffuser size exactly to your hose size to prevent leaks)

Specifications

• Type: Inline CO₂ diffuser (external)
• Material: Acrylic body + ceramic diffusion disc
• Installation: Filter return hose (outflow side)
• Working Pressure: ±1.5 bar recommended
• Compatibility: Pressurised CO₂ systems with regulator
• Sizes:
  • M: 12/16mm
  • L: 16/22mm

Ideal For

• High-tech planted aquariums
• Aquascaping display tanks
• Canister filter systems
• Hobbyists wanting hidden CO₂ equipment
• Medium to large aquarium setups

Why Choose an External CO₂ Diffuser?

Compared to in-tank diffusers, external (inline) diffusers provide better efficiency, cleaner aesthetics, and more stable CO₂ levels. By dissolving CO₂ before it enters the tank, you reduce visible bubbles and improve overall distribution—making it the preferred choice for serious aquascapers.

Quick Size Guide

• Running 12/16mm hoses (e.g. smaller Oase, Sunsun, etc.) → Choose M
• Running 16/22mm hoses (e.g. larger canister filters) → Choose L