Airmax Shallow Water Series Aeration System
Bottom-Diffused Aeration for Ponds 6 ft and Under
The Airmax Shallow Water Series is Airmax's purpose-built diffused aeration system for ponds up to 6 ft deep. Standard aeration systems are engineered around deep-pond hydraulics - drop a diffuser in a shallow pond and the compressor loafs, the airline weight is overkill, and you pay for horsepower you can't use. The SW Series solves that with a low-restriction linear-diaphragm compressor sized to shallow-pond back pressure, a matched pair of ProAir 2 weighted membrane diffusers, and 3/8-inch weighted airline. Aeration you actually get to use on ponds that other systems overpressurize.
Pick the SW20 for ponds up to a quarter acre - LR25 compressor delivers 2.5 CFM to 2 diffusers, pulls 0.43 amps at 115V, and runs $3.60 a month at 10 cents per kWh. Step up to the SW40 for ponds up to a half acre - LR50 compressor delivers 4.9 CFM to 4 diffusers at 0.87 amps, roughly $7.20 a month. Both use the same faux-rock composite cabinet, dual air filters, cooling fan with rain shroud, pre-wired ETL-certified electrical, and quick-disconnect airline fittings.
Pick your airline package based on how far the diffuser locations sit from the cabinet. The SW20 ships with 0, 100, or 200 ft of weighted airline; the SW40 ships with 0, 200, or 400 ft. All rolls are kink-free, fish-hook resistant, self-weighted, and carry a 5-year airline warranty. Every system is manufactured in Armada, Michigan and backed by Airmax's category-leading warranties.
Aeration for ponds up to 6 ft deep. The Airmax Shallow Water Series is a purpose-built diffused aeration system with a compressor sized to shallow-pond back pressure, ProAir 2 weighted membrane diffusers, and 3/8-inch weighted airline. Aeration engineered for shallow ponds, not deep-pond hardware you can't fully use.
Pick SW20 for ponds up to 1/4 acre - LR25 compressor, 2.5 CFM, 2 diffusers, roughly $3.60/mo. Step up to SW40 for ponds up to 1/2 acre - LR50 compressor, 4.9 CFM, 4 diffusers, roughly $7.20/mo. Same faux-rock composite cabinet, cooling fan, ETL-certified pre-wired electrical.
Pick your airline package based on distance to diffuser drop points. SW20: 0/100/200 ft. SW40: 0/200/400 ft. All rolls kink-free, self-weighted, 5-year airline warranty. Made in Armada, MI.
Free shipping on every SW kit. Call (470) 354-1969 for sizing help.
See the SW Series in Action
SW20 vs SW40 Comparison
| SW20 | SW40 | |
|---|---|---|
| System |  |
 |
| ProAir 2 Diffusers | 2 | 4 |
| Max Pond Size | Up to 1/4 Acre | Up to 1/2 Acre |
| Maximum Depth | 6 ft | |
| SilentAir Compressor | LR25 | LR50 |
| Airflow | 2.5 CFM | 4.9 CFM |
| Running Amps | 0.43 A | 0.87 A |
| Voltage | 115 V | |
| Wattage | 50 W | 100 W |
| Monthly Operating Cost* | $3.60 | $7.20 |
| 3/8" EasySet Weighted Airline | None, 100 ft, or 200 ft | None, 200 ft, or 400 ft |
| Cabinet Dimensions | 23" L x 17" W x 15" H, faux-rock composite | |
| Power Cord | 6 ft | |
Requirements & What to Know Before You Buy
- Pond Depth: maximum 6 ft. The SW Series compressors are tuned to low back pressure. Deeper ponds need Airmax PondSeries (PS10 / PS20) or ProSeries aeration systems.
- Pond Size: SW20 handles up to 1/4 acre with 2 diffusers; SW40 handles up to 1/2 acre with 4 diffusers. Larger water bodies need to move up to PondSeries diffused aeration.
- Cabinet Location: the ETL-certified composite cabinet sits on the shore within 6 ft of a standard 115V GFCI outlet (the included power cord is 6 ft). Level ground helps but is not critical - the cabinet has an elevated base and rain-shroud fan intake.
- Cabinet Elevation: the cabinet's elevated base protects against occasional standing water but not against submersion. Site above the shore's normal high-water mark.
- Diffuser Locations: place ProAir 2 diffusers at the deepest points of the pond. Two diffusers on the SW20 typically go on opposite sides of the pond; four on the SW40 space evenly around the pond perimeter.
- Airline Distance: measure from the cabinet's intended location to each diffuser drop point through any conduit runs. Add 5-10 ft of slack per run. Order the airline package that covers the total measured length.
- Electrical: standard 115V GFCI-protected household outlet. SW20 draws 0.43 amps (50W), SW40 draws 0.87 amps (100W). Both run continuously 24/7 at these low draws.
- Airline Type: both systems use 3/8-inch EasySet self-weighted airline. Kink-free, fish-hook resistant, sinks on its own without adding weights - just uncoil into position at the deepest point.
- Winter Operation: most owners run the system year-round. In freezing climates, the continuous circulation keeps a hole open in the ice for gas exchange and prevents winterkill.
- Sizing Help: Call (470) 354-1969 with your pond dimensions, depth, and shoreline layout and we will confirm SW20 or SW40 and the right airline package.
What's Included & Optional Add-Ons
- SilentAir Linear-Diaphragm Compressor - LR25 on the SW20, LR50 on the SW40; rubber-mount vibration dampeners for whisper-quiet operation
- ProAir 2 Weighted Diffuser Plates - 2 on the SW20, 4 on the SW40; membrane-stick design, integrated check valve, self-weighted sled
- Composite Cabinet - ETL-certified, faux-rock finish, elevated base, ventilation fan with rain shroud, 23 x 17 x 15 in
- Dual Air Filters - top and side high-density intake filters protect the compressor
- Quick-Disconnect Airline Fittings - factory-installed at compressor and diffusers
- Pressure Gauge and Relief Valve - built into the cabinet manifold
- Enhanced Cooling System - fan pulls filtered air across the compressor, extends compressor life in hot summers
- Optional 3/8" Weighted Airline - SW20: none / 100 ft / (2) 100 ft rolls; SW40: none / (2) 100 ft / (4) 100 ft rolls
- Optional Additional Diffusers - can add extra diffusers up to the manifold port count (SW20: 2 ports; SW40: 4 ports); sold separately
- Optional Airflow Manifold Assembly Upgrade - Airmax 2-port (SW20) or 4-port (SW40) manifold; sold separately
Shallow Water Series Specifications
| Manufacturer | Airmax, Inc. (Armada, Michigan) |
| Models | SW20 (600801, 600803), SW40 (600811, 600813) |
| Type | Bottom-diffused shallow-pond aeration system |
| SW20 Compressor | Airmax SilentAir LR25 linear-diaphragm, 2.5 CFM |
| SW40 Compressor | Airmax SilentAir LR50 linear-diaphragm, 4.9 CFM |
| Voltage | 115 V, 60 Hz (GFCI-protected outlet required) |
| SW20 Running Amps | 0.43 A |
| SW40 Running Amps | 0.87 A |
| SW20 Wattage | 50 W |
| SW40 Wattage | 100 W |
| Monthly Operating Cost | SW20: ~$3.60 | SW40: ~$7.20 (at $0.10/kWh, 24/7 run) |
| Maximum Depth | 6 ft |
| SW20 Pond Size | Up to 1/4 acre with 2 diffusers |
| SW40 Pond Size | Up to 1/2 acre with 4 diffusers |
| Diffusers | ProAir 2 weighted membrane-stick, integrated check valve, self-weighted sled |
| Airline | 3/8" EasySet self-weighted, kink-free, fish-hook resistant |
| Airline Options | SW20: none / 100 ft / (2) 100 ft rolls | SW40: none / (2) 100 ft rolls / (4) 100 ft rolls |
| Cabinet | Composite, faux-rock finish, ETL-certified, 23 L x 17 W x 15 H |
| Power Cord | 6 ft |
| Warranty - ProAir 2 Diffuser | 5 years |
| Warranty - Compressor and Electrical | 3 years |
| Warranty - Composite Cabinet | 10 years |
| Warranty - EasySet Airline | 5 years |
| Applications | Backyard residential ponds, koi ponds, agricultural stock ponds up to 1/2 acre and 6 ft deep |
| Country of Origin | Made in USA (Armada, MI) |