An aquafeed plant and a pond farm need different buildings

By Johnny Joe, export engineer at Hebei Hongji Shunda Steel Structure Engineering Co., Ltd. · 25 October 2026 · 6 min read

Aquaculture operations need feed, and feed is either bought or made on site. Where it is made on site, the plant is a feed mill with the same problems as any other: dust, moisture and heavy loads.

The farm itself is open water. The buildings on it are stores, pump houses, a hatchery, and a processing shed if the operation harvests and packs.

An aquafeed mill is a dry building in a wet place

Feed ingredients must stay dry, and the mill produces dust. That makes the feed building a sealed, dry envelope — which is the opposite of what most of the rest of the site needs.

The conflict is humidity. A farm next to open water has high ambient humidity, and a dry store in that environment needs a vapour barrier and, often, dehumidification. A steel building without one will condense on the underside of the roof and drip onto the product.

Pelleting puts load on the floor, not the roof

A pelleting line is vertical: conditioning, pressing, cooling, crumbling and screening happen in a stack. That weight arrives at the floor on a small footprint.

The building therefore needs a floor designed for the equipment and a height that accommodates the stack and the maintenance access above it. As with any mill, the eave follows the machine, not the other way round.

Pump houses are the most corrosive buildings on the site

A pump house sits at the water's edge, handles water continuously, and is often poorly ventilated because it is small and rarely visited.

That combination — constant humidity, splash, and no air movement — is the harshest corrosion environment on a farm. The building should be detailed as a wet, saline environment even where the water is fresh, because the local humidity and the spray behave the same way.

The site is the design

Pond farms are laid out around water levels, access bunds and the sequence of filling and draining. The buildings are small objects placed on that layout, and their position matters more than their structure.

Where a store or a pump house ends up below the pond level, the building is designed around a flood risk that was created by the layout. Getting the levels right is free at planning stage.

Processing on site changes the building brief

If the operation harvests, ices, packs or freezes on site, a processing building is added — and that is a wet food building with hygiene zoning, drainage and cold rooms, not a farm shed.

That is a different project and it should be defined as one from the start, rather than added to the farm brief later.

What I want before drawings

• Whether feed is made on site, and the mill capacity.
• The equipment stack heights and footprints in the mill.
• The humidity the store must be held at, and how.
• The pump house positions relative to water level.
• Whether any processing happens on site.
• The wind speed for the site in km/h from the applicable local code, not a round number.

Aquaculture buildings are small and scattered, which makes them easy to design badly one at a time. Treating the mill, the stores and the pump houses as one coordinated set is what keeps the site working.