Designing a Formal Koi Pond

In the heart of Richmond, Virginia, a residential property underwent a remarkable transformation. What began as a maintenance challenge for a koi enthusiast evolved into a full-scale, formal aquatic showcase. At the center of it all: nearly 200 adult koi.

This exceptional home had long featured a large, picturesque pond. However, despite its beauty, the original feature was never designed with koi in mind. It lacked proper filtration, sufficient depth, and predator protection—making it difficult to maintain a secure, healthy environment for such an extensive fish collection.

While exploring ways to retrofit the existing layout, a new idea emerged: construct a purpose-built koi pond from the ground up. With full creative and technical control, we designed a 100,000-gallon formal koi pond that would become the new home for the client’s treasured collection. Reimagined as a tranquil water garden, the original pond now flourishes with lotus and pond lilies.

Designed With Purpose, Built for Beauty

This new pond needed to achieve two critical goals: provide a high-quality, sustainable environment for koi and integrate seamlessly into the existing landscape. It needed to be large, crystal clear, easy to maintain and visually compelling from every angle.

After multiple design consultations, the final specifications were set. The pond would span approximately 85 feet in length, 30 feet in width, and reach a depth of 5 to 6 feet. A slightly organic shape was selected to offer dynamic sightlines and a natural aesthetic. With a total volume of roughly 100,000 gallons, the pond comfortably houses the client’s current koi collection and offers room to introduce additional high-end Japanese koi over time.

Strategic placement was also important. The location allows for maximum sun exposure, optimal viewing from key points on the property, and a seamless connection to the surrounding landscape design.

Precision Timing and Thoughtful Transitions

We strategically scheduled construction for winter 2023–2024, with completion targeted by Easter. This timing wasn’t arbitrary as spring offers ideal conditions for relocating koi, thanks to mild water temperatures that reduce fish stress. Additionally, it allowed the biological filtration system time to mature just in time for the seasonal increase in feeding and fish activity.

While the build was underway, my team and I continued to provide daily care for the client’s koi. A key component of the transition involved prophylactic parasite treatments and the relocation of approximately 75 koi to an offsite holding facility. This move helped prepare space for a new shipment of imported Japanese koi scheduled to arrive in April.

Underground Strategy, Above-Ground Elegance

Before breaking ground, the team carefully navigated around existing underground utilities. Rather than incur the costs and delays of relocating infrastructure, the pond’s design was adapted to work around it—preserving both the project timeline and budget.

Once excavation began, we dug and poured a frost-depth footer to support the structural walls. The perimeter was built using CMU block walls, which were solid-filled and reinforced with vertical rebar in every other cell. These walls extended 18 inches above grade, ultimately forming a 20-inch seat wall when capped—providing a functional and elegant viewing space for visitors.

The raised wall also adds an element of formal design, creating clear architectural lines that define the pond’s footprint while inviting engagement from guests and family members.

Filtration Powerhouse: Clean Water by Design

The backbone of this pond’s performance lies in its carefully engineered filtration system. Ten Evolution Aqua aerated bottom drains were installed across the pond floor to ensure complete debris removal. These drains eliminate the formation of “dead zones” where waste can accumulate.

To complement the bottom intake, we positioned four no-niche skimmers to capture floating debris and organic matter. From there, water travels nearly 80 feet downhill through a network of 4-inch PVC lines to a dedicated 30-by-15-foot filtration pad, discreetly screened by evergreen hedging.

At the filtration pad, water is gravity-fed into six independent systems, each composed of:

• Evolution Aqua Cetus Sieve pre-filters

• PerformancePro Artesian2 external pumps

• 36-inch Evolution Aqua K+ Advanced pressure filter

• Dual Evolution Aqua EvoUV 110-watt clarifiers

The combined filtration system provides 1,320 watts of ultraviolet sterilization which is crucial for a pond that sits in full sun. This ensures superior water clarity and prevents the formation of green water or algae blooms. Clean water returns through surface and midwater return jets, designed to maintain robust circulation throughout the entire pond.

A Touch of Formal Charm

A decorative water feature, incorporated iat the primary viewing area, enhances the pond’s visual appeal. This centerpiece serves both aesthetic and functional purposes. It increases aeration, aids in water circulation and elevates the formal feel of the space.

The feature includes a copper-finished scupper wall by Atlantic Water Gardens, flanked by three copper spillway bowls. The motion and sound of cascading water add a sensory dimension to the landscape, while the symmetry and placement of the elements reinforce the pond’s classical design.

A Vision That Continues to Grow

Projects of this scale offer more than just a construction opportunity—they mark the beginning of an evolving relationship between the contractor and the client. We believe the completion of a pond is not the end of a project, but the start of a long-term partnership.

Unlike traditional garden ponds, formal koi ponds demand regular, attentive care. As clients develop a deeper appreciation for koi keeping, their interest in water quality, fish health and ongoing upgrades often grows. This can lead to monthly or even weekly service programs, new koi acquisitions, and further enhancements to the pond system.

For pond builders and service professionals willing to go the extra mile—sourcing Japanese koi, offering long-term care, and providing advanced filtration expertise—results in a client relationship built on trust, shared passion and continued investment.

A Living Feature That Redefines the Property

This koi pond is more than a backyard improvement—it’s a living, breathing ecosystem designed with care and precision. For the homeowner, it represents a dream fulfilled. For the koi, it offers a sanctuary that meets the highest standards of health and safety. This project demonstrates what’s possible when innovation, engineering and artistry converge.

About the Author

Cooper Sallade is the founder of Aqua Fauna, Inc., a full-service construction and maintenance company specializing in water features. In addition to custom water feature construction and pond maintenance, the company also has a retail sales outlet, and providdes koi sourcing trips to Japan.