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HBV-21 Koi Pond Kit – Up to 5,000 Gallons

Build a Koi Pond Designed Around the Needs of Koi

A dedicated koi pond is more than a deep water garden.

The HBV-21 Koi Pond Kit is designed from the beginning as a complete koi pond filtration, circulation and aeration system. It combines surface skimming, bottom-drain waste removal, pre-filtration, bead filtration, UV clarification and aeration in one customizable package.

Choose your pond size, pump and other available options, and we'll configure the components to work together as a complete system.

Designed for koi. Designed for routine maintenance. Designed to take the guesswork out of building your own koi pond.

Choose the Koi Pond Size That Fits Your Landscape

The HBV-21 Series is designed for koi ponds up to 5,000 gallons, with three popular pond dimensions:

• 8' × 10' × 4' deep
• 10' × 12' × 4' deep
• 12' × 14' × 4' deep

Our Kit Builder selections allow you to configure the system for the pond you want to build.

Liner, underlayment, aeration and other size-dependent components can be matched to your selected pond size.

What Makes This a Koi Pond Kit?

A dedicated koi pond is designed very differently from a traditional water garden pond.

Instead of covering the pond floor with rock and gravel, a koi pond has a smooth, bare liner bottom sloped toward a bottom drain. There are no submerged rocks, gravel or planting areas for waste to collect within.

The bottom drain continuously draws settling fish waste and debris from the pond floor toward the HydroSieve™ pre-filter, while the HydroClean™ pond skimmer removes floating leaves and debris from the surface.

Both water sources feed the external pump, and a 3-way valve allows the flow between the skimmer and bottom-drain circuit to be balanced.

The water is then filtered, clarified and returned to the pond.

Rather than allowing waste to accumulate inside the pond, the entire system is designed to move waste out of the pond and into accessible filtration equipment where it can be removed.

HydroBead Vortex™ Filtration

At the heart of the HBV-21 system is our HBV-21 HydroBead Vortex™ Koi Pond Filter, designed for koi ponds up to 5,000 gallons.

The HydroBead Vortex™ provides both mechanical and biological filtration in an external filter that can be routinely backwashed.

That means the filtration system can be cleaned without draining the koi pond or disturbing the fish.

Bottom-Drain Pre-Filtration

Fish waste and other heavy debris naturally settle toward the bottom of a koi pond.

The pond floor is sloped toward a 3" bottom drain, which carries that waste toward the HydroSieve™ Bottom Drain Pre-Filter.

The HydroSieve™ captures debris before it reaches the pump and HydroBead Vortex™ filter, where it can be easily removed during routine maintenance.

It's a simple principle:

Remove the waste from the pond instead of allowing it to accumulate in the pond.

Surface Skimming + Bottom-Drain Circulation

A Seagull HydroClean™ Pond Skimmer continuously removes floating leaves and surface debris while the bottom drain collects settling waste below.

The external pump draws from both through a 3-way control valve, allowing you to balance circulation between the surface and bottom of the pond.

Three pond returns help distribute the filtered water and create additional circulation throughout the pond.

The result is water movement designed to help carry debris toward the equipment intended to remove it.

UV Clarification & Aeration Included

Every HBV-21 Koi Pond Kit also includes a 36-watt UV clarifier to help control free-floating algae and maintain clear water.

A properly sized external aeration system supplies additional oxygen and water movement for the pond. The appropriate aeration system is matched to the pond size you select in the Kit Builder.

Filtration removes waste.

UV helps maintain water clarity.

Aeration supplies oxygen and improves circulation.

A properly designed koi pond needs all three.

What's Included?

Your HBV-21 Koi Pond Kit includes the major components needed to build a complete koi pond filtration system:

• HBV-21 HydroBead Vortex™ Koi Pond Filter
• Seagull HydroClean™ Pond Skimmer
• HydroSieve™ Bottom Drain Pre-Filter
• 3" Bottom Drain
• Choice of External Pump with Leaf Trap
• Check Valve Assemblies
• 3-Way Flow-Control Valve
• 36-Watt UV Clarifier and Plumbing Components
• External Aeration System
• 45 mil EPDM Pond Liner
• Protective Underlayment
• Flexible PVC Plumbing
• Three Pond-Return Plumbing Assemblies
• PVC Glue, Primer and Silicone
• Required System Fittings and Connections

Specific sizes and quantities are determined by the options you select in the Kit Builder.

3" bottom-drain pipe is not included because of the high cost of shipping long lengths of large-diameter rigid pipe. It is readily available locally from plumbing suppliers and major home-improvement stores.

In-Ground, Above-Ground or Somewhere In Between

Your koi pond doesn't have to look like everyone else's.

An HBV-21 system can be used with an in-ground koi pond, raised koi pond, or a design combining both.

The structure surrounding the water may change, but the basic koi pond principles remain the same: a smooth unobstructed interior, a bottom sloped toward the drain, effective surface and bottom circulation, external filtration, UV clarification and aeration.

That gives you considerable freedom to design the pond to complement your home and landscape.

A Complete System Instead of a Collection of Parts

Designing a koi pond piece by piece means determining pump flow, filtration capacity, plumbing sizes, bottom-drain requirements, aeration, UV sizing, liner dimensions and how all those components work together.

We've already done that work.

The HBV-21 Koi Pond Kit Builder lets you customize the system for your project while starting with components designed to function together.

Not Sure Which Options to Choose?

We're happy to help.

Tell us the dimensions of the koi pond you're planning, your desired construction style and any special features, and Russell Watergardens can help you determine the appropriate HBV-21 configuration.

Build the pond you want—with a filtration system designed specifically for koi.

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What Is a Koi Pond?
(And Why It's Not the Same as a Water Garden Ecosystem Pond)

A koi pond can best be described as a swimming pool for koi or a large, purpose-built tank designed specifically for raising healthy koi. It is very different from a water garden pond, which is primarily designed as a decorative landscape feature.

Water garden ecosystem ponds are designed to look natural in the landscape. Koi ponds are designed for the raising of healthy koi in a more formal pool in the landscape.

Understanding this difference is extremely important before building a pond for koi. Many installation contractors that don't understand the difference between the two often build water garden ecosystem ponds for customers that asked for, wanted, and preferred a koi pond. Sadly, many contractors have been sued for installing the wrong kind of pond.

It is of the utmost importance to understand the differences between a water garden ecosystem pond and a koi pond. They are not the same.

Koi Pond vs. Water Garden Pond

Koi Pond:

A true koi pond is engineered for fish health, water quality, and predator prevention, while a water garden pond focuses on plants, rocks, and aesthetics.

Typical features of a true koi pond include:

• Smooth pond bottom (no rocks or gravel)
• Smooth straight-down sides for predator prevention
• No marginal plant shelves
• Nothing in the pond a koi could harm itself upon
• Bottom drains for continuous waste removal
• External filtration systems
• External pumps
• External air pump
• UV system

Water Garden Ecosystem Pond:

Water garden ponds are designed to look natural in the landscape with boulders, aquatic plants, and rock and gravel.

Typical features of a water garden ecosystem pond include:

• External, non-backwashable biological waterfall filters
• External pond skimmer
• Boulders on all vertical walls
• Aquatic planting shelves stepped down into the pond
• Rock and gravel covered bottoms
• No bottom drain
  
• Submersible or external pumps

Koi ponds and water garden ecosystem ponds look different, have different filtration systems, and have different aesthetic designs than each other. Water garden ecosystem ponds are not the same as koi ponds.

Many koi clubs across the country explain that a koi pond is not the same as a water garden ecosystem pond. If you are unsure, check with your local koi club through the Associated Koi Clubs of America (AKCA.org).

While koi can survive in some water garden ponds for a while, they typically do not provide the healthiest long-term environment for raising big, beautiful koi.

How Koi Ponds Are Designed

Unlike water garden ponds (also known as ecosystem ponds), koi ponds are designed more like swimming pools integrated into the landscape.

Koi ponds may be built:

• Completely underground
• Partially above ground
• Fully above ground

They are typically constructed using concrete, concrete block, or structural framing that retains the surrounding soil while a liner, concrete, or polyurea coating holds the water.

Most koi ponds are 3-4 feet deep at a minimum, though many serious koi keepers prefer 5-6 feet or deeper. Greater depth helps protect fish from predators and allows koi to grow larger and healthier.

Koi ponds may include a waterfall, but in many cases waterfalls are not used as part of the filtration system.

Koi Pond Filtration and Water Quality

High-quality koi ponds rely upon external filtration systems designed for easy maintenance and excellent water clarity.

Our Ultimate Koi Ponds use our advanced filtration components such as:

• HydroBead™ Vortex backwashable filters for biological and micro filtration
• HydroClean™ fish-safe, dry-hands serviceable pond skimmers for surface debris removal
• Bottom drains for continuous sunken debris removal
• HydroSieve™ bottom drain pre-filters for mechanical filtration

Oxygen is supplied through an external aeration system, while water circulation is powered by external pumps. Because these systems are located outside the pond, no high-voltage electrical equipment sits in the water.

Some systems can also incorporate Bubble-Less™ aeration technology, allowing crystal-clear viewing of the koi without surface bubbles.

Are Koi Ponds Landscape Features?

Unlike water garden ponds, koi ponds are not primarily landscape features. Instead, they function more like formal aquatic structures, similar to swimming pools designed specifically for fish.

Landscaping can still be incorporated around the koi pond, but the koi pond itself remains optimized for fish health and water quality rather than aquatic plant displays.

Koi Pond Maintenance

One of the advantages of a properly designed koi pond is simple maintenance.

Typical koi pond routine maintenance includes:

• Empty the HydroClean™ pond skimmer weekly
• Empty the HydroSieve™ bottom drain pre-filter weekly
• Backwash the HydroBead™ Vortex koi pond filter monthly

Bottom drains and skimmers continuously remove debris, preventing the buildup of waste that would otherwise require draining and cleaning the pond.

During filter backwashing, some pond water is replaced with fresh water through an automatic water fill valve inside the HydroClean™ pond skimmer, helping maintain ideal water conditions for koi. Backwashing the filter creates small water changes each time the filter is backwashed.

Without waterfalls, koi ponds are also quiet and peaceful, allowing owners to enjoy watching their koi fish glide calmy through crystal clear water.

Where Can You Install a Koi Pond?

Koi ponds can be installed in many types of outdoor spaces, but several factors should be considered:

• Adequate yard space for proper pond size
• Good visibility from patios or viewing areas
• Level ground for easier construction
• Avoiding heavily shaded locations

With thoughtful placement, a koi pond can become a beautiful centerpiece of an outdoor living area.

Can Other Fish Live in a Koi Pond?

Koi ponds can support other compatible fish species, such as goldfish, but not all pond fish are suitable companions.

Before introducing new fish, research their compatibility with koi and consider how they may affect pond maintenance and filtration requirements.

How to Start Your First Koi Pond

The first step in building a koi pond is careful planning.

Most importantly, remember that a koi pond is not the same as a water garden pond. Many pond kits marketed as "koi ponds" are actually designed for water garden ponds.

To start your koi pond project:

1. Choose the right location
2. Decide on the pond size and depth
3. Calculate the total water volume
4. Select the proper size filtration system
5. Construct the pond structure and plumbing.

Get Help Planning Your Koi Pond
Tell us about the pond you're planning, and we'll help you determine the right system for your project

Only after the pond is fully built and the filtration system is operating should you introduce koi fish into their new habitat.

A properly designed koi pond provides the safest, healthiest environment for raising koi, allowing these beautiful fish - often called "living jewels" to grow large, vibrant, and strong.

This screenshot is from Aquascape's own website. They make the claim that "koi ponds, also called water gardens ....". This is flat out a false statement. We know of several contractors that have been sued for installing a water garden pond for their customers that wanted a koi pond. A koi pond is nothing like a water garden pond. Yes, you can have koi in a water garden pond, but a water garden pond is not a koi pond or the healthiest choice for raising koi. If you are unsure, contact a local koi club in your area and ask them: "Is a koi pond the same as a water garden pond?". Or: "Is an Aquascape type water garden ecosystem pond the same as a koi pond?". They will tell you that they are not the same - they are completely different types of ponds.

A koi pond can have waterfalls, but in most cases, the waterfalls are not part of the filtration system like those found in Water Garden Ponds, Hybrid Ponds™ or CrossOver Ponds™.

A Koi Pond is not a "landscape" item like Water Garden Ponds, Hybrid Ponds™, or CrossOver Ponds™, but more of a pool or large fish tank specifically designed for keeping Koi.

Our Ultimate Koi Pond Kits are biologically and micro filtered with super efficient, easy to clean HydroBead Vortex™ filters, along with HydroClean™ pond skimmers, bottom drains, and HydroSieve™ bottom drain pre-filters performing the mechanical filtering duties.

Oxygen for the Koi Pond is provided by an aeration system, and the water is pumped with an external pump. No high voltage electrical devices are in the water.

The Koi Pond is constructed with either concrete, concrete blocks, or timbers retaining the earth "outside" the pond and have rubber liner, concrete, or polyurea liner holding the water "inside" the pond.

Landscaping can be placed up to and overhanging the Koi Pond. Maintenance of Koi Ponds is very easy. Simply backwash the HydroBead Vortex™ filter at least every 30 days, rinse the HydroClean™ pond skimmer and HydroSieve™ bottom drain pre-filter elements at least every seven days.

A Koi Pond without waterfalls is a quiet, peaceful pond with beautiful Koi gliding about in blissful silence. All the oxygen in the Koi Pond is supplied by the aeration system. The pond can be lit at night with underwater lighting so the pond owner can view the beautiful Koi at night.

The bottom drain and pond skimmer constantly remove waste and debris from the pond, so the pond doesn't have to be drained for cleaning like typical Aquascape water garden ponds.

Nitrates are removed from the water during the backwash cycles. As pond water is used to clean and rinse the HydroBead™ Vortex filters, new water is replaced in the pond by an automatic water fill valve inside the HydroClean™ pond skimmer.

The water in the Koi Pond is circulated with an external pump, and the aeration system supplies the oxygen. Both units are external and can be placed anywhere outside and away from the pond. This makes for a clean and formal look to the Koi Pond as the filtration units can be placed far away from the pond and out of view.

Koi Ponds are constructed for the sole purpose of raising and keeping koi. They are the ideal pond style for those that want the best and safest pond available for their beloved koi.

The depths of the Koi Pond allow the koi to grow large and strong. The filtration system is external, so it can be easily increased in size as the koi grow in size or numbers. Koi truly are the "Swimming Jewels". The Koi Pond is the safest environment to keep these jewels.

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