Kasco Surface Aerator 1/2 HP

The Kasco surface aerator 1/2 HP is a self-contained floating unit that pushes water into the air through a single open propeller, rapidly transferring oxygen into your pond while keeping the entire water column mixed. Built by Kasco Marine and backed by an independent Auburn University study showing up to 3 lbs of oxygen delivered per horsepower per hour, the 2400AF is one of the most efficient surface aerators on the market — ideal for ponds and small lakes up to about 1/2 acre.

Smith Creek Field Notes

The Kasco surface aerator 1/2 HP is the simplest way to add oxygen to a pond — no plumbing, no diffuser lines on the bottom, just float it, anchor it, and plug it in. We recommend the 1/2 HP Kasco for smaller ponds where fish kills, summer algae blooms, or stagnant water near the surface are the main concern. If your pond is deeper than about 6-8 feet or you're managing muck on the bottom, a diffused (bottom) aeration system will do more for your water overall — but for quick surface circulation, oxygen boosts during hot weather, and breaking up thermal stratification near the surface, this is hard to beat. The optional bottom screen is worth adding if you stock fish — it keeps curious koi and larger fish away from the propeller.

Is This Right for Your Pond?

✅ The Kasco surface aerator 1/2 HP is the right choice if:

• Your pond or tank is approximately 1/2 acre or smaller
• Water depth is at least 15 inches at the aerator location
• You want fast surface oxygenation and circulation without installing bottom diffuser lines
• You're dealing with summer oxygen crashes, odor, or early signs of algae from stagnant water
• You have access to a 120V GFCI-protected outlet near the pond

⚠️ Keep in mind:

• This unit is 120V only — there is no 240V version of the 1/2 HP model
• If you stock fish, especially koi, add the bottom screen variant to keep fish away from the propeller
• Cord lengths of 150 ft. and 200 ft. include a quick-disconnect fitting at the control end, making it easy to disconnect the unit for winter storage or maintenance without rewiring
• For ponds deeper than 6-8 feet or with significant bottom muck, a diffused aeration system will outperform a surface aerator — see our diffused aeration systems

How It Works

The Kasco surface aerator 1/2 HP (model 2400AF) uses a single open propeller mounted beneath a floating housing. As the propeller spins, it draws water up and sprays it into the air in a fine pattern of droplets. This dramatically increases the surface area of water exposed to the atmosphere, allowing oxygen to dissolve into the water far faster than it would through surface contact alone. The agitation also circulates the oxygenated water throughout the pond, breaking up the stagnant, oxygen-poor layers that form near the bottom and along the edges during hot weather.

This process helps reduce odor from decomposing organic matter, discourages algae growth by disrupting the still-water conditions algae prefers, and keeps dissolved oxygen levels more stable for fish — especially overnight and during summer heat when oxygen depletion is most dangerous.

Specifications

Full specifications for the Kasco surface aerator 1/2 HP (model 2400AF):

*150 ft. and 200 ft. cord lengths include a quick-disconnect fitting for easy seasonal removal.

Choose Your Configuration

The Kasco surface aerator 1/2 HP is available in four cord lengths — 50, 100, 150, and 200 feet — to match the distance from your power source to the pond. Choose whether you want the unit with or without a bottom screen:

• Without Screen — standard configuration, suitable for ponds without large fish or where the propeller area is not a concern
• With Screen — adds a protective bottom screen that keeps debris, leaves, and fish away from the propeller. Recommended for koi ponds and any pond with fish you don't want near moving parts

What's Included

Every Kasco surface aerator 1/2 HP order includes:

• Kasco 2400AF 1/2 HP surface aerator unit with float
• Two 50 ft. mooring lines
• Power cord in your selected length (50/100/150/200 ft.)
• Replaceable sacrificial zinc anode
• Bottom screen (if selected)

Not included: control panel. The optional Kasco C-25 control panel adds GFCI protection, a 24-hour timer, and a photocell-controlled outlet for optional lighting — see our aeration parts and accessories to add one.

Pair With

Add nighttime visual interest with pond and lake fountain lighting — the C-25 control panel includes a photocell-controlled outlet made for this. For ponds also dealing with muck or nutrient buildup, pair surface aeration with beneficial bacteria treatments — the bacteria work faster with the extra oxygen this aerator provides. Browse our full surface aerators collection for other HP sizes, or see diffused aeration systems for deeper ponds.

Frequently Asked Questions

What size pond is the Kasco 1/2 HP surface aerator good for?

The Kasco surface aerator 1/2 HP (model 2400AF) is designed for ponds and tanks up to approximately 1/2 acre. For larger water bodies, consider stepping up to a 3/4 HP, 1 HP, or larger model — Kasco's general rule of thumb is roughly 1 HP per surface acre, though pond depth, shape, and stocking density can shift that estimate.

Do I need the bottom screen?

The bottom screen is recommended if you stock fish, especially koi or larger species that might approach the propeller out of curiosity. It keeps debris and fish away from the moving parts without reducing aeration performance. If your pond has no fish or only small fish that stay near the surface, the standard unit without a screen works fine.

What voltage does this aerator use?

The 1/2 HP Kasco surface aerator is 120V, single phase, 60Hz only — there is no 240V version of this model. It must be plugged into a properly grounded, GFCI-protected 120V outlet.

How deep does the water need to be?

This aerator can operate in water as shallow as 15 inches. There's no maximum depth requirement — the unit floats at the surface regardless of total pond depth.

What's the difference between the cord length options?

Cord length should match the distance from your power source to where the aerator will float in the pond, plus some slack for positioning. The 50 ft. and 100 ft. cords are standard. The 150 ft. and 200 ft. cords include a quick-disconnect fitting, which makes it easy to unplug and remove the unit for winter storage or maintenance without having to rewire any connections.

Will the Kasco surface aerator 1/2 HP help with algae?

Yes, indirectly. By keeping the water circulating and well-oxygenated, surface aeration disrupts the stagnant conditions that algae thrives in and helps prevent the oxygen crashes that can lead to fish kills during algae die-off. For active algae problems, pair this aerator with aquatic algaecides or beneficial bacteria for longer-term nutrient control.

Can this aerator run continuously?

Yes — Kasco surface aerators are designed for continuous 24/7 operation. The heavy-duty, corrosion-resistant motor is built for dependable long-term use in both fresh and saltwater environments.

Does this come with a control panel?

No, the control panel is sold separately. The Kasco C-25 control panel is the recommended option for 1/2 HP units — it includes GFCI protection, a 24-hour timer, and a photocell-controlled outlet for optional lighting. See our aeration accessories to add one to your order.

Is this aerator safe for saltwater or brackish ponds?

Yes. The 2400AF is built with a heavy-duty, corrosion-resistant motor and includes a replaceable sacrificial zinc anode specifically for use in saltwater or other corrosive environments. The zinc anode should be inspected periodically and replaced as it wears.

Seasonal Notes

Spring

Spring is an ideal time to install or restart a surface aerator. As water warms, oxygen demand increases and stratification begins to form — early aeration helps prevent the spring oxygen swings that can stress fish coming out of winter dormancy.

Summer

Peak season for the Kasco surface aerator 1/2 HP. Warm water holds less dissolved oxygen, and calm summer conditions allow stagnant layers to form quickly. Continuous operation during summer helps prevent the overnight oxygen crashes that are the leading cause of summer fish kills.

Fall

Continue running the aerator through fall — circulation helps prevent early ice formation around the unit and keeps oxygen levels stable as falling leaves and dying vegetation add organic load to the pond.

Winter

In climates where the pond freezes, the 1/2 HP surface aerator can help keep a small area of open water if positioned correctly, but it is not designed as a dedicated de-icer. If using a 150 ft. or 200 ft. cord, the quick-disconnect fitting makes it simple to remove the unit for winter storage. For dedicated winter ice management, see our de-icers and circulators.

Browse Related Products

Looking for a different size? Explore other HP options in our surface aerators collection beyond the Kasco surface aerator 1/2 HP, add fountain lighting for nighttime display, or pair with beneficial bacteria treatments for complete pond management. For deeper ponds, see our diffused aeration systems.