2 Way Air Manifold with 8mm to 14mm Outlets

Air Manifold 18mm Inlet to 4mm, 8mm, 10mm, 12mm or 14mm 2 Way

2 way air manifold with adjustable ball valves for pond aeration systems

The Air Manifold 18mm Inlet to 4mm, 8mm, 10mm, 12mm or 14mm 2 Way is a practical air distribution fitting designed to split airflow from 1 pond air pump into 2 separate airline runs. It is ideal for pond aeration systems where you need to operate 2 air stones, 2 diffusers, 2 aerated filter chambers or 2 airline feeds from a single air source.

Each manifold has an 18mm inlet, making it easy to connect to many pond air pumps using a suitable flexible rubber boot. The outlet tails then change depending on the option selected, allowing you to choose between 4mm, 8mm, 10mm, 12mm or 14mm tails to suit the airline being used.

Each outlet also features its own ball valve, allowing the airflow to each airline to be individually adjusted. This is especially useful when balancing air between 2 different diffusers, air stones or filter chambers. For example, 1 airline may be longer than the other, or 1 diffuser may sit deeper in the pond, which can naturally affect the amount of air it receives. The built in valves allow you to fine tune the airflow so both outlets perform as required.

This makes the manifold much easier to match to your pond setup. The larger 18mm inlet provides a straightforward connection from the air pump, while the 2 smaller outlet tails allow the air to be distributed to the correct airline size. The adjustable valves then give you extra control over how the air is shared between the 2 outlets.

The 4mm outlet option is suited to smaller airline, compact air stones, aquariums, quarantine tanks and light duty aeration systems. The 8mm outlet option is suitable for standard pond airline, pond air stones, diffuser discs and many koi pond aeration setups. The 10mm outlet option is designed for larger airline, heavier duty sinking airline, larger diffusers and higher airflow pond systems.

Good aeration is important for fish health, biological filtration and overall water quality. Koi, pond fish and beneficial filter bacteria all rely on dissolved oxygen, especially during warmer weather when oxygen levels can fall. By splitting airflow between 2 separate outlets, this manifold allows a single air pump to supply more than 1 area of the pond or filtration system.

It can be used with standard pond airline, weighted sinking airline, air stones, ceramic diffusers, moving bed filters and aerated biological chambers. For a neat underwater installation, it can be paired with Air Aqua Standard Sinking Airline or Evolution Aqua Premium Heavy Duty Sinking Airline, depending on the airline size and strength required.

Key benefits

• Splits airflow from 1 air pump into 2 outlets
• 18mm inlet for easy connection using a suitable rubber boot
• Selectable outlet tails in 4mm, 8mm, 10mm, 12mm or 14mm
• Each outlet has its own ball valve
• Allows airflow to be controlled and balanced
• Suitable for pond air pumps, air stones and diffusers
• Helps run 2 aeration points from 1 air source
• Useful for koi ponds, fish ponds and aquariums
• Suitable for aerated filters and quarantine systems
• Simple to install
• Helps improve aeration layout flexibility
• Ideal for new installations, upgrades and repairs

Reasons to buy

This 2 way air manifold is a useful fitting when you want to split air from a single pump into 2 separate airline runs. It gives you more control over where air is delivered and allows 1 air pump to operate multiple aeration points.

The adjustable ball valves make it easier to balance airflow between the 2 outlets. This is useful if you want 1 diffuser to receive more air than the other, if 2 airline runs are different lengths, or if the diffusers are positioned at different depths.

It is particularly useful if you want to place air stones in different areas of a pond, run 2 diffuser discs, supply air to both a pond and filter chamber, or improve an existing aeration layout without adding another air pump.

The 18mm inlet also makes the pump connection simple when used with a suitable flexible rubber boot, while the outlet tail options allow you to select the correct size for your airline.

Choosing the correct size

The inlet side of the manifold remains the same across all 3 options.

Inlet size: 18mm

Connection type: Suitable for connection to many pond air pumps using a flexible rubber boot

The size selected refers to the 2 outlet tails.

4mm outlet tails
Suitable for smaller airline, aquarium air systems, compact air stones, quarantine tanks and light duty aeration setups.

8mm outlet tails
Suitable for standard pond airline, pond air stones, diffuser discs, koi pond aeration systems and aerated biological filters.

10mm outlet tails
Suitable for larger airline, heavy duty sinking airline, larger diffusers, higher airflow systems and more demanding pond aeration installations.

Always choose the manifold outlet size to match the airline you plan to use. You should also check the air pump connection, airline size and diffuser connection before ordering.

Suitable applications

• Koi pond aeration
• Garden pond aeration
• Fish ponds
• Quarantine tanks
• Aquarium air systems
• Pond air stones
• Ceramic air diffusers
• Aerated biological filters
• Moving bed filters
• Pond oxygenation systems
• Aquaculture systems
• Pond maintenance and repairs

Product specifications

• Product type: 2 way air manifold
• Available sizes: 4mm, 8mm and 10mm
• Application: Air distribution and airflow splitting
• Suitable for: Pond air pumps, airline, air stones, diffusers and aerated filters
• Outlet quantity: 2 outlets
• Installation type: Inline airline fitting

Installation guidance

Choose the correct manifold size to suit the airline being used.

Push the airline securely onto each connection point.

Ensure all connections are firm before switching on the air pump.

Position the manifold where it can be accessed for future checks and adjustments.

Use suitable airline clips if required for a more secure connection.

Using larger airline with this manifold

The 12mm and 14mm outlet options are useful on larger pond and lake aeration systems where a bigger airline or trunk line is being split into separate diffuser runs. For very heavy underwater runs, compare this manifold with our Super Heavy Duty Weighted Airline, which has a 1/2 inch internal diameter and is supplied in 30 metre lengths. Always check the airline diameter, barb size and clamp arrangement before installation.

Related 8mm outlet manifold

For systems that need one larger inlet feeding four 8mm outlet lines, see the 4 Way Air Manifold with 8mm to 14mm Inlet and 8mm Outlets. It is useful when a main 8mm, 10mm, 12mm or 14mm air feed needs to be split neatly to four 8mm diffuser or airline runs.