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The Kasco RA4 Aeration System is well suited to aerating larger ponds up to 4 acres in size based on a depth of 15' or greater. Less depth will reduce the coverage area.

Effective aeration can be achieved in 3 acre ponds 5 to 8 feet deep, 4 to 5 acre ponds 8 to 12 feet deep, and 6 to 7 acre ponds 12 to 16+ feet deep.

Please contact us if you have questions or would like a certified aerial pond mapping (no charge) to be conducted to find out if this system will fit your pond the best.

The two 1/4 HP compressors in the kit draw 5.1 amps on a 120v, and 2.6 amps on the optional 230v configuration (contact us if you require 230v).

Air output is 6.4 cfm's at 10 psi.

Maximum operational depth is 50'

The Robust-Aire RA4 system includes:
• Two KM-60 model ¼ HP Teich-Aire compressors. Cabinet is optional (see below). Weather protection for the pump is required.

• Two dual-port aluminum manifolds with valves

• Four Robust Aire diffuser assemblies

• The images above are for illustrative purposes only. No airline is included in this package which allows customers to only order what they may need. For any tubing run from the compressor to the diffuser that's under 300' you can use 3/8" airline. For any run greater than 300', please use 5/8" to maintain better airflow to the diffuser.

Order Airline Here: https://americanaeration.com/weighted-kink-proof-airline-optional/

Additional Information

Robust-Aire Diffusers

Robust-Aire diffusers are the most efficient on the market and create more water flow to aerate your pond. Diffusers are designed to provide a fine air bubble with the least amount of pressure. The base is made of thick HDPE plastic and a locking fill plug allows you to fill it with pea gravel or other weighted substrate. It has a raised design that keeps the diffusers performing at an optimal level above the pond bottom. A durable, bolted, strain relief attachment ensures that the weighted tubing will not become detached during installation or maintenance. A check valve with Viton seals keeps water from entering the tubing when the system is not operating.


The RA4 is available with two options for enclosures - this type of pump does require protection from the elements. As quoted the standard RA4 system includes the base mount "ground" cabinet. If you have an existing shed or outbuilding to house the pumps, please contact us for a custom "no-cabinet" option and save money.

A large base mount cabinet is suggested as the default method for the system.
• Dimensions are 26” x 21” x 20”H
• Molex connection inside the cabinet.
• Fans provide 370 CFM ventilation and are paired with the compressors.
• Compressors are mounted at the factory in the cabinet.

No Cabinet (NC): This is desired when installing the compressor system in your own structure. Compressors need to be kept out of the weather and supplied with active ventilation. A galvanized mounting bracket system is included with each compressor to allow mounting to a floor, wall, or pedestal. Rubber mounting feet and all hardware are included as well. Remote manifold is easily mounted via wood screws

Sure Sink weighted tubing is available in easy to handle 100 foot coils.

RA systems 4-6 do not include airline allowing for the customer to order only what they need or require. To order click on the related products tab above.

Each coil is boxed and includes our full packet of barbed connectors and adapter fittings, and tubing clamps. You will be prepared to make any connection necessary with the tubing kit. Additional 3/8 or 5/8 Sure Sink weighted tubing is available when additional length is needed.

All tubing is also available in 500 foot reels. Reels do not include fittings.

Teich-Aire rocking piston compressors

• Provide efficient, continuous-duty operation with minimal maintenance and quiet operation. Units are extremely quiet.
• Included pressure relief valve
• Air filter with replaceable cartridge
• Sound level is less than: 70 dB without cabinet (Window air conditioner), 65 dB with cabinet and acoustic sound proofing (Normal conversation) Updated June 2020 - Now 34% quieter with the new air filter intake module!
• Safely starts under pressure. Maximum operating depth 40 feet.


  • Compressors
    • 3 years on motor (increased from 2 years)
    • 2 years on piston cups and gaskets
  • Weighted Tubing
    • 15 years(increased from 10 years)
  • Diffuser

    • Lifetime(increased from 5 years)

  • Post Mount and Base Mount Cabinets
    • Lifetime(increased from 5 years)

Customer Reviews

Based on 1 review Write a review
Kasco Marine RA4 Robust-Aire Diffused Aeration System - Airline Sold Seperately

Customer Reviews

Based on 1 review
Marlon S.
Saved My Fish

We have had fish losses here each of the last two summers when things got hot so I wanted to get this installed in the spring. Our pond is around 2 acres but it's only 8 feet deep or so, and after consulting with Mark, the RA4 sounded like a good fit. Installation was not really complicated...it just took a few extra hands to help. I've had the aerator going through some spells of 90+ degrees now and the fish are doing well...no losses! Hope we can keep this going now.

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