Water Features & Koi Ponds

Properly Filtered. Properly Wired. Built to Hold Water.

Paragon designs and builds koi ponds, pondless waterfalls, fountains, and stream features for South Bay homes, with the filtration, electrical, and edge detailing that keep them running clear instead of turning green or leaking into the yard. Almost every failed water feature we're called to repair traces back to three things: an undersized pump or filter, a liner or shell that was never detailed properly at the edges, and electrical that was never done to code. We size pumps and filtration to the water volume, run equipment on GFCI-protected circuits and permit new ones, and build every feature as a recirculating system — which is what California's water-waste rules expect of decorative water.

Choosing the Right Water Feature

Our Water Feature Build Process

1. 01Site review — we look at sun exposure, slope, soil, nearby trees and leaf drop, distance to power, and where overflow water can safely go.
2. 02Feature selection and sizing — we match the feature type to how much maintenance you want, then calculate water volume, pump flow, and filtration capacity.
3. 03Permits and approvals — new electrical circuits, deeper excavations, and any Palos Verdes-area HOA design review are identified and handled before digging starts.
4. 04Excavation and shell — the basin is dug with proper shelves and depth, then lined with underlayment and liner or built as a reinforced concrete shell, with edges detailed above the water line.
5. 05Plumbing, filtration, and electrical — bottom drains, skimmers, filters, UV, and auto-fill are plumbed, and GFCI-protected power is run to the equipment by licensed electrical trades.
6. 06Stone, planting edge, and lighting — boulders and rock are set to conceal liner edges and equipment, with low-voltage underwater and landscape lighting where you want it.
7. 07Fill, run-in, and handoff — the system is filled, leak-checked, and run so the water can establish before any fish go in, and we walk you through cleaning, filter service, and seasonal care.

Water Feature Capabilities

• Custom koi pond design and construction
• Pondless and disappearing waterfalls
• Waterfall and stream features
• Courtyard fountains and bubbling urns
• Mechanical and biological filtration systems
• UV clarifier installation
• Bottom drains, skimmers, and auto-fill valves
• Pump sizing, replacement, and plumbing
• GFCI-protected outdoor circuits and weatherproof outlets (permitted)
• Low-voltage underwater and landscape lighting
• EPDM liner and reinforced concrete pond shells
• Boulder, stone, and heavy statue placement
• Leak detection, edge repair, and resealing
• Existing pond rebuilds and conversions to pondless

How Paragon Builds Water Features

• Pumps and filtration sized to the actual water volume, not to a kit off the shelf.
• Electrical done to code — GFCI protection, weatherproof covers, and permits for new circuits.
• Recirculating designs that work with California water-waste rules and local restrictions.
• Licensed, insured contractor based in Torrance, with 18+ years of South Bay work.

Water Features & Koi Ponds — Frequently Asked Questions

How much does a koi pond or water feature cost in the South Bay?

Typical South Bay ranges run about $3,500–$12,000 for a self-contained fountain or small pondless waterfall, $12,000–$35,000 for a larger pondless waterfall or stream, and $25,000–$80,000 or more for a custom koi pond with bottom drains, multi-stage filtration, and substantial stonework. Repairs and rebuilds of existing features commonly run $1,500–$10,000. Depth and volume, excavation access, boulder tonnage, filtration equipment, lighting, and whether a new electrical circuit has to be run all move the number. Paragon gives a fixed quote after a site visit rather than a per-square-foot guess.

How deep should a koi pond be?

A common guideline for koi is around three feet deep in at least part of the pond, and serious keepers often go deeper. Depth buffers summer temperature swings, dilutes waste, and gives fish somewhere to go when raccoons or herons visit — steep sides help for the same reason. Plant shelves around the perimeter can be shallower. Keep in mind that deeper standing water can raise permit or safety-barrier questions in some cities, particularly with young children in the household, so we confirm what your city requires before we finalize depth and edge design.

Why does my pond keep turning green?

Green water is usually a bloom of free-floating algae driven by sunlight, excess nutrients, and filtration that can't keep up. The usual causes are an undersized pump or filter, too many fish for the volume, overfeeding, and debris decomposing on the bottom. A UV clarifier kills free-floating algae as water passes through it, while proper mechanical and biological filtration removes the nutrients feeding it, and shade and good circulation help. Dumping in chemicals without fixing the system buys a few weeks at a time. We diagnose the cause before recommending equipment, because the fix is often plumbing and sizing rather than chemistry.

Do I need a permit for a water feature?

Many small fountains and pondless waterfalls don't need a building permit on their own, but the electrical usually does when we add a circuit or an outdoor outlet for the pump. Larger ponds, retaining walls around a feature, grading, and deeper excavations can require permits or barrier review depending on the city, and Palos Verdes-area HOAs may require design approval before anything is built. Requirements differ between Torrance, Redondo Beach, the beach cities, and unincorporated county areas, so we confirm what applies to your parcel during planning and pull whatever the work requires.

Are water features allowed with South Bay watering restrictions?

Generally yes, as long as the feature recirculates. State water-waste rules prohibit using potable water in decorative fountains and features that don't recirculate, and local water suppliers can add their own restrictions during a shortage. A well-built recirculating feature only loses water to evaporation and splash, and a pondless design loses less than an open pond of the same footprint. An auto-fill valve handles normal top-off, and a sudden jump in water use usually means a leak worth chasing. We design to current rules and suggest confirming any temporary restrictions with your water provider.

Can you fix a leaking pond or waterfall?

Usually. Most leaks aren't holes in the middle of a liner — they're at the edges, where the liner has settled below the water line, or in the waterfall and stream section where water finds its way around the liner. Cracked plumbing fittings and failed skimmer or drain seals are the next most common culprits. We isolate the source by shutting the pump down and watching where the water level stops dropping, then repair the edge, fitting, or liner section. If the original build was undersized or poorly detailed, a rebuild or a conversion to a pondless waterfall is often the better investment.

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