Charles Austen ETD200A Pond Air Pump

Charles Austen ETD200A Pond Air Pump

The Charles Austen ETD200A Pond Air Pump is a high output double diaphragm air pump with built in low pressure alarm. It is designed for large ponds, lakes, koi systems and sewage treatment plants where strong airflow is needed and where a fault warning would be valuable.

This model combines the airflow performance of the ETD200 with the added reassurance of an integrated alarm. If the airline becomes restricted, a diffuser blocks or pressure drops, the alarm helps make the issue easier to spot. This is particularly useful on sewage and septic systems because the pump is often installed where it will not be checked every day.

For pond use, the alarm can also be valuable on larger koi ponds, lake aeration systems or biological filters that depend on constant air supply. The double diaphragm design delivers strong, oil free airflow while the weather resistant casing makes the pump suitable for indoor or outdoor installation.

Key features

• High output double diaphragm air pump with built in alarm
• Low pressure fault warning for large pond and treatment plant installations
• Suitable for large ponds, lakes, koi systems and sewage treatment plants
• Strong airflow from a compact footprint
• Oil free air delivery for clean biological aeration
• Weather resistant casing for indoor or outdoor installation
• Serviceable design with replacement service kits available

Technical overview

• Model: Charles Austen ETD200A
• Product type: Oil free double diaphragm air pump with built in low pressure alarm
• Maximum airflow: 200 litres per minute at 0.15 bar
• Power consumption: Approximately 160W
• Power supply: 220V to 240V 50Hz
• Connector size: 18mm
• Noise level: Approximately 45 dB(A)
• Dimensions: 360 x 220 x 200mm
• Weight: Approximately 13.6kg
• Alarm type: Built in low pressure alarm with buzzer and LED warning light
• Common uses: Pond aeration, koi filter aeration, septic systems and sewage treatment plants

Compare Charles Austen air pump ranges

Browse the full Charles Austen ET Series, Charles Austen ETA Series, Charles Austen ETAO Series, Charles Austen ETX Series and Charles Austen CP Series air pumps.

What do A and AO mean? Standard ET models provide reliable continuous aeration. The A versions add a built in low pressure alarm with a loud buzzer and LED warning light. The AO versions add the same built in alarm plus a 230V output cable for connecting to an external alarm panel or beacon. A and AO pumps are generally used on sewage treatment plants and septic systems because the air pump may be out of sight and a fault may not be noticed quickly, but they can also be used on pond systems where extra warning is useful.

Should I choose ETD or standard ET?

The ETD range is useful where you need strong airflow from a compact pump body, particularly on specialist wastewater systems, larger aeration layouts, lake aeration or installations where a compact high output unit is required.

For most pond aeration, koi pond air systems and biological filter aeration, we would usually recommend the standard Charles Austen ET range instead. The standard ET pumps are the main continuous duty aeration range, are widely used on ponds, are easy to service and run quieter than the ETD models at the equivalent 200 litres per minute size. The standard ET200 is listed at approximately 40 dB(A), while the ETD200 is listed at approximately 45 dB(A).

Technical details

• Product: Charles Austen ETD200A Pond Air Pump
• Brand: Charles Austen
• SKU / product code: ETD200A
• Type: treatment equipment
• Check model size, flow rate, connection size and compatibility before ordering.
• Install with suitable supporting equipment and allow access for future servicing.

Related standard ET options

• Charles Austen ETD200 Pond Air Pump if you want the ETD version without the built in alarm.
• Charles Austen ET200 Pond Air Pump for most standard pond aeration, koi filters and general continuous air supply.
• Charles Austen ET200A Pond Air Pump if you want the standard ET200 with a built in low pressure alarm.
• Charles Austen ET200AO Pond Air Pump if you want the standard ET200 with an alarm and 230V external output.

Maintenance and servicing

Charles Austen state that Pro Series air pumps should be serviced yearly to validate the motor warranty. You can view the correct Charles Austen Air Pump Service Kit options in one place, including genuine replacement diaphragm, filter and valve kits for compatible Charles Austen Enviro ET, ETA, ETAO and ETD models where available. Regular servicing helps maintain airflow, reduce the risk of diaphragm failure and keep your pond, koi or treatment plant air pump running efficiently.

Recommended air diffusers and airline

To get the best performance from this air pump, pair it with suitable large pond and lake air diffuser stations and weighted airline. As a guide, each 10 inch diffuser disc normally works best with around 40 to 50 litres per minute of air. Most single diffuser stations are rated at around 30 to 60 litres per minute, so matching the number of diffuser discs to the pump output helps keep airflow balanced and efficient.

• Suggested diffuser setup: 4 diffuser discs are normally a good match. View the Charles Austen DS4 or Charles Austen DSW4 diffuser station.
• Air manifolds: If you need to split airflow from one pump across multiple airline runs, use the Air Manifold 4mm/8mm/10mm – 2 Way for two runs or the Air Manifold 4mm/8mm/10mm – 4 Way for up to four runs. For Charles Austen air pumps, the 8mm or 10mm outlet options are normally the best choice. The 4mm option is better kept for short, small air stone runs rather than larger diffuser stations.
• Standard sinking airline:
  4mm/8mm Standard Sinking Airline is a practical choice for smaller pond air runs. On Charles Austen pumps we would normally use the 8mm option where possible.
• Heavy duty sinking airline:
  Evolution Aqua Heavy Duty Sinking Airline is the better choice for larger ponds, longer airline runs and high output pumps. For larger Charles Austen pumps, the 8mm or 10mm option is normally the better choice to reduce restriction.
• Super heavy duty weighted airline:
  For long, permanent underwater runs to large diffuser stations, consider our Super Heavy Duty Weighted Airline. Its 12.5mm internal bore helps reduce friction loss compared with smaller airline, and the weighted 30m construction keeps the hose on the pond or lake bed. Use the correct outlet adaptor or manifold and confirm the diffuser connection size before ordering.

Charles Austen recommend that Enviro air pumps are serviced at least every 18 months. On hard working pond, koi and treatment plant systems, regular servicing helps maintain airflow, reduces the risk of diaphragm failure and supports the manufacturer warranty requirements. Service kits are available for the main ET, ETA, ETAO, ETD and ETX models where applicable.

If you are unsure which service kit suits your pump, contact us and we can help match the correct kit to your Charles Austen model.

Complete your Charles Austen aeration setup

A good aeration system is not only about choosing the air pump. Airline size, diffuser choice, manifold layout and routine servicing all affect the real airflow that reaches the pond. Use the links below to build a complete system rather than buying the pump in isolation.

• Browse the full Charles Austen range
• Browse pond air pumps
• Charles Austen air pump service kits
• Large pond and lake diffuser stations
• Standard sinking airline
• Heavy duty sinking airline
• 2 way air manifold
• 4 way air manifold