The Pool Leak Pros Call (239) 533-5935
Call or text (239) 533-5935

Pool leak guide

Why does my pool only lose water when the pump is running?

If your pool holds its level with the pump off but drops while it runs, the leak is usually in the plumbing, not the pool shell. Here is how to narrow it down before you call.

Why the pump makes a difference

When the pump runs, it pushes water under pressure through the return lines and any water features. A crack in that plumbing leaks much faster under pressure. With the pump off, the pressure drops and the leak slows or stops.

Common causes

  • A broken return line under the deck or pavers
  • A leaking waterfall, sheer descent or fountain line
  • A cracked fitting or flex pipe at the equipment pad
  • A leaking valve or pump seal

Test it yourself

Do a bucket test twice: once with the pump on its normal schedule, and once with it off. If you have a water feature, run one more test with the feature off. Write down the results for each, and turn off your auto-fill during the tests.

What we check

We check the equipment pad first, because a leaking valve or pump seal is easy to mistake for a pool leak. Then we isolate and pressure test each line and listen for the break so we only open the deck right over it.

Need a straight answer?

Call or text (239) 533-5935 or request service. Leak detection starts at $295.

Pool losing water? Get a straight answer.

Leak detection from $295. Non-commissioned leak techs. Florida license CPC1460553.