Why is my pool losing water?
Separate evaporation, splash-out and equipment discharge from a leak that needs measured testing.
Use this guide to
Record useful evidence, complete safe checks and recognise when the pool or equipment should remain out of use.
Important limit
A symptom helps narrow the fault. It does not prove which part has failed, whether the water is safe, or whether underground pipework is sound.
Safety first
Do not let the water fall below the skimmer opening while the pump is scheduled to run. If the pump is drawing air or running without a full water supply, switch it off at the normal isolator and arrange inspection.
Start with context
Observe before changing settings
A falling waterline is evidence of water loss, not proof of where the water is going. Weather, swimmer use, backwashing, an overflowing waste line, a plumbing fault and a shell leak can produce similar observations. Record the loss before choosing a repair.
Safe first checks
Observation is not confirmation
What the signs actually mean
A symptom is just a clue. We still need to test the system properly before we rip anything out or start pouring chemicals in.
| What you observe | What may cause it | What confirms the next step |
|---|---|---|
| Loss is similar with the pump on and off | Evaporation, shell fitting, light niche, tile-line, hydrostatic or structural leakage. | A controlled level record and staged isolation testing are needed. A bucket comparison can indicate whether the pool is losing more than a nearby water surface, but it does not locate the leak. |
| Loss increases while circulation runs | Pressure-side plumbing, filter, heater, chlorinator housing, return fitting or waste-line discharge. | Inspect the operating equipment pad and waste outlet, then isolate hydraulic sections and pressure test where required. |
| Loss appears greater while the system is off | Suction-side plumbing, water-level fitting, shell penetration or a fault below the static waterline. | Record the resting level and isolate lines. The final level may narrow the elevation of a leak but does not prove which component has failed. |
| Air appears in the pump lid or returns | Low water, blocked skimmer, suction restriction, lid seal, valve or suction-side air entry. | Restore a safe water level and inspect accessible seals and baskets before vacuum and line testing. Air alone does not confirm a water leak. |
Practical sequence
Complete only the checks that are safe
Record
Use the same marked point and photograph the level at the same time each day. Note rain, heat, wind and pool use.
Inspect
Check visible equipment, waste discharge and nearby ground without opening pressurised housings or electrical panels.
Protect
Top up enough to keep the skimmer supplied. Switch the pump off if it cannot hold prime or begins drawing air.
Test
Book measured leak detection when loss exceeds the weather and use pattern or continues after obvious discharge is stopped.
Stop and arrange help
Do not keep operating or dosing through these conditions.
What remote review can do
Review a level log, weather notes, equipment photos and video of visible discharge.
Help decide whether to stop circulation and what area should be tested first.
Identify obvious operating errors such as an incorrect multiport position from a clear photo.
What cannot be confirmed remotely
Locate an underground leak, prove a shell defect or determine pipe integrity from water-loss rate alone.
Distinguish every evaporation pattern from leakage without controlled observations.
Confirm that one wet area is the only fault in a connected hydraulic system.
Prepare useful evidence
Clear records reduce guesswork. They do not replace on-site testing where pressure, flow, electrical condition or water integrity must be measured.
Related help
Continue with the right service or tool
Real questions
Frequently asked questions
Where an answer depends on a measurement or site condition, the limit is stated.
How much water loss is normal?+
There is no single normal daily figure. Surface area, water temperature, air temperature, wind, humidity, cover use and swimmer activity all matter. Compare a measured pool loss with local conditions rather than relying on a generic number.
Does a bucket test find the leak?+
No. A controlled comparison may show that the pool is losing more water than an exposed container, but it does not identify whether the fault is in the shell, fittings, equipment or plumbing.
Should I keep topping the pool up?+
Maintain enough water for safe circulation, but record additions. Repeatedly adding water can hide the loss rate and alter chemistry. Switch circulation off if the pump is drawing air.
Can dye confirm a leak?+
Dye may show local movement at a suspected static point when the water is still, but random dye use does not test buried pipework and can give misleading results around normal circulation.
Need measured confirmation?
Send the observations before the visit
Include the address, equipment labels, wide photos, close photos, readings and what changed before the problem started. Palatial Pools will confirm what can be checked remotely and what needs an on-site test.