
Learn the common types of koi pond leaks and how we find the source fast to protect your fish, water level, and pond system.
Because the exact source and extent of a leak cannot be determined visually, all leak detection and subsequent repair services are billed on a Time & Materials (T&M) basis. This ensures you only pay for the exact time and materials required to resolve your specific issue.
Initial Service Charge: $375 — This includes our travel trip fee and covers the first hour of on-site diagnostic investigation.
Additional Time: $150 per hour — Billed in equitable increments for any additional time required for deep diagnosis or physical repair work.
Materials: All specialized components, liners, sealants, or plumbing fittings used during the repair will be itemized and billed transparently.
Our Promise: We keep you completely in the loop. If our technicians discover major structural failures or extensive damage that requires a significant overhaul, we will pause work, present our findings, and obtain your explicit approval before proceeding with major material expenses.
Finding a leak isn't about guesswork—it's about gathering precise data. Water features are complex, interconnected systems, and rushing into a repair without a full diagnostic assessment usually results in missed issues, wasted materials, and ongoing frustration.
Here is exactly how we approach leak detection and why our systematic process saves you time and money.
Before we pick up a shovel or mix any sealants, we gather baseline data.
The "Multiple Leak" Reality: It is incredibly common for a system to have more than one leak (for example, a structural crack in the waterfall and a loose fitting behind the skimmer). If we fix the first problem we see without testing the rest of the system, your water level will keep dropping.
Isolating the Variables: By monitoring water levels, pressure testing plumbing lines, and systematically shutting down components, we isolate sections of your pond to confirm exactly where water is—and isn't—escaping.
Our technicians use a combination of advanced equipment and structural expertise to pinpoint failures:
Assessing the Leak: Before we begin hunting for the exact location of a leak, we must first measure how much water your system is actually losing. This quantitative data is crucial for two reasons: it confirms the severity of the issue, and it gives us a benchmark to prove the leak is 100% resolved after the repair.
Establishing a Baseline: By measuring the exact drop in inches per hour or day, we establish a baseline. If your pond is losing 2 inches of water a day, and we find a loose fitting that only accounts for a half-inch drop, our data tells us there is still another leak hidden elsewhere.
Post-Repair Verification: Once repairs are complete, we run the same measurement test again. We don't consider the job done until the data proves your water level is perfectly stable (minus evaporation).
System Component Isolation: We turn off specific elements (like waterfalls or filtration loops) to see if the leak persists when certain plumbing lines are inactive.
Linear Structural Inspection: We meticulously inspect liner edges, rock transitions, and penetrations to ensure shifting ground hasn't created a hidden low spot or spillover.
Pressure Testing: We test underground and hidden plumbing lines to ensure they are holding pressure and completely airtight. (if required)
Once our data collection is complete, we don't just tell you there's a leak—we show you the big picture. We provide a clear assessment of your system’s overall integrity, allowing us to map out a definitive, permanent repair strategy rather than a temporary patch.
Sometimes, a dropping water level isn't a hidden leak at all—it can be caused by simple environmental factors or minor maintenance issues. Before scheduling a diagnostic visit, check these common culprits:
The Splash-Out Test: Check your waterfall or stream rocks. Over time, shifting rocks or growing plants can redirect water flow, causing it to splash over the liner edge rather than back into the pond.
The "Pump Off" Test: Turn off your pump for 24 hours (make sure to keep an eye on your fish and provide alternative aeration if needed). If the water stops dropping while the pump is off, the leak is likely located in your filtration system, waterfall, or plumbing lines, rather than the main pond basin.
Evaporation Check: During hot, dry, or windy days, a healthy pond can lose up to a 1/4 inch of water per day naturally due to evaporation.
If you’ve checked these areas and your water level is still dropping significantly, it’s time for a professional assessment.
1. Low Liner Edges & Settling (The Most Common)
As the ground shifts over time under the weight of rocks and water, the perimeter liner can settle or push downward.
The Culprit: Water simply flows over a newly created "low spot" in the liner edge and enters the surrounding soil.
Where it Happens: Most frequently along stream beds, waterfall edges, or where heavy boulders sit on the pond rim.
2. Plumbing & Fitting Failures
Pond plumbing is constantly under pressure and exposed to changing ground temperatures.
The Culprit: PVC pipes can crack from shifting soil, or glue joints can fail. Additionally, freeze-thaw cycles can cause rigid fittings to split.
Where it Happens: Flex-pipe connections, check valves, or underground plumbing lines connecting the pump to the biological filter.
3. Equipment & Structure Penetrations
Anywhere the liner has been intentionally cut to attach a piece of equipment is a high-risk zone for a leak.
The Culprit: Silastic sealants degrade over time, or faceplate screws rust and loosen, breaking the watertight seal against the liner.
Where it Happens: Skimmer faceplates, mechanical biofilters (waterfall tubs), bottom drains, and underwater lighting penetrations
4. Wildlife & Pest Damage (Rodent & Animal Chewing)
Critters can do a surprising amount of damage to a water feature's infrastructure, often while looking for a drink or trying to nest.
The Culprit: Rodents (like rats, mice, or gophers) can chew completely through flexible PVC pipe and EPDM rubber liners. Additionally, larger wildlife like raccoons or dogs can puncture shallow liner edges with their sharp claws while entering or exiting the pond.
Where it Happens: Exposed flexible plumbing lines under decks, buried lines near rodent burrows, or shallow beach areas and shelves where animals gather.
5. Ground Movement & Root Intrusions
Nature is constantly shifting, and what was perfectly level five years ago might not be level today.
The Culprit: Aggressive tree or bamboo roots can grow directly underneath the pond, putting immense pressure on the liner until it stretches to a breaking point or pushes a fitting out of alignment. Severe ground settling or minor seismic shifts can also pull underground pipe joints apart.
Where it Happens: Sections of the pond built close to large trees or invasive perimeter landscaping.
6. Mechanical Pre-Filter & Auto-Fill Malfunctions
Sometimes the leak isn't a hole at all, but a failure in how water is managed or automatically replenished.
The Culprit: If you have an automatic water leveler (auto-fill) that becomes stuck or jammed, it can cause the pond to constantly overflow its edges. Alternatively, a clogged pre-filter or skimmer basket can back up water, forcing it to spill out over the top of the equipment faceplate instead of flowing through the system.
Where it Happens: Directly inside the skimmer vault, auto-fill valves, or external pressure filter canisters.