Why Is My Pool Losing Water?
Before assuming your pool has a plumbing leak, use a simple process to separate normal evaporation from a skimmer leak, equipment-pad issue, return fitting problem or structural water loss.
Some summer water loss is normal evaporation. If your pool loses noticeably more water than a bucket of pool water sitting beside it, or if water loss changes depending on whether the pump is running, you may have a leak in the skimmer, plumbing, return line, equipment pad or pool shell.
Start With the Bucket Test
The bucket test does not tell you the exact leak location. It tells you whether the water loss is likely normal evaporation or more than evaporation.
Set a bucket on a pool step and fill it with pool water.
Mark the pool water level outside and bucket water level inside.
Run your normal pool schedule and avoid topping off the pool.
More pool loss than bucket loss points toward a leak.
Where Pools Commonly Lose Water
Faceplates, gaskets, weirs, cracks and old skimmer bodies can all create water-loss paths.
Pump lids, unions, valves, filters, drain plugs and fittings can drip only while the system runs.
Loose fittings, cracked fittings and wall penetrations can leak at or below the waterline.
Vinyl liner punctures, structural cracks and light niches can be harder to spot but still matter.
Skimmer Leak Clues to Watch For
| What You Notice | Possible Area | What to Inspect |
|---|---|---|
| Water stops dropping at skimmer level | Skimmer throat, gasket, faceplate or body | Look for cracks, loose screws, warped faceplate and failed gasket compression. |
| Water loss is worse while the pump runs | Pressure-side plumbing or equipment pad | Check valves, unions, pump lid, filter drain and visible plumbing connections. |
| Water loss is worse with pump off | Suction-side plumbing or pool structure | Inspect skimmer, suction fittings, main drain area and visible shell/liner defects. |
| Air bubbles in pump basket | Suction-side air leak | Inspect pump lid O-ring, skimmer water level, valves and suction-side fittings. |
Common Product Paths Before Replacing a Whole Skimmer
A leak does not automatically mean the entire skimmer needs replacement. Start with the actual failed component when fitment is known.
Useful when the issue is damaged access hardware or poor debris flow.
A broken weir can affect surface draw and skimmer performance.
Critical on vinyl-liner and compatible skimmer assemblies where seal compression matters.
Use only when the body itself is cracked or physically damaged.
Unions, valves and fittings may solve equipment-pad leaks without replacing major equipment.
Helpful for isolating specific lines during a proper pressure or leak test.
When You Should Call a Leak Professional
The bucket test clearly shows the pool losing more water than evaporation alone.
You have checked the pad, skimmer and fittings but cannot see a clear source.
Pressure testing and line isolation are needed to locate underground failures accurately.
Pool Water Loss FAQ
How much pool water loss is normal in summer?
Can a skimmer leak cause my pool water to keep dropping?
Why does my pool lose more water when the pump is on?
Why does my pump basket have air bubbles?
Need Help Identifying a Skimmer or Leak-Related Part?
Send Aqua Terra Backyard photos of the skimmer, pool wall opening, equipment pad, any visible crack, and the model number from the current component.
Shop Pool Skimmers Shop Skimmer PartsThis guide is for education and product planning. Structural leaks, underground plumbing leaks and electrical-equipment concerns should be evaluated by a qualified pool professional.