First: is it a leak or evaporation?
Use the bucket test. Fill a bucket with pool water and stand it on the top step, so it sits at the same temperature and in the same sun and wind as the pool. Mark the water level inside the bucket, and mark the pool level on the tile or the weir. Switch off any automatic top-up, run the pump as normal, and compare the two after 24 to 48 hours.
If both have dropped by about the same amount, you are seeing evaporation. If the pool has dropped clearly more than the bucket, you have a leak. Repeat the test with the pump off for the same period: if the pool loses less with the pump off, the leak is probably in the plumbing that is under pressure when the pump runs.
Where pool leaks usually are
Most leaks are in a handful of predictable places. Checking those first is what makes leak detection efficient rather than a matter of digging up the garden.
- The weir: cracks where the weir meets the pool shell, often after ground movement
- Light niches: the conduit and seal behind an underwater light
- Return fittings and aimflows where they pass through the shell
- Cracks in the shell itself, especially in older pools
- The multiport valve leaking to waste through a worn gasket
- Pipe joints at the pump and filter, and underground pipe runs
How we find it
We start with the easy wins: the equipment. A worn multiport gasket that sends water to the backwash line, or a dripping joint at the pump, is visible once you know where to look. If the equipment is sound, we move to the pool itself.
Dye testing shows where water is escaping through the shell: a small amount of coloured dye released close to a suspected crack or fitting is drawn toward the leak if water is moving through it. We work around the weir mouth, the light niche, the returns and any visible cracks. Where the pump-on and pump-off results point to the plumbing, the lines are isolated and checked one at a time to narrow the leak down to a section of pipe.
The result is a location and a recommendation, not a guess. Sometimes the fix is a seal or a fitting we can do on the day. Sometimes it is a pipe under paving or a crack that needs a proper repair, and we quote that in writing.
Signs you should not ignore
Some symptoms mean water is going somewhere it should not, and the longer it continues the more it can cost. Wet patches in the lawn or paving near the pool that do not dry out, soft ground, cracks appearing in paving or coping, and the auto-top-up running constantly all deserve attention.
Air in the pump basket and weak flow can point to a leak on the suction side, where air gets in rather than water getting out. That kind of leak costs filtration rather than water, and it often shows up as a pool that is harder to keep clear.
Fixing the leak
Once the leak is found, most repairs are straightforward. Weir cracks can be sealed, light niche seals can be redone, fittings replaced and small shell cracks patched. Plumbing leaks mean opening up the pipe at the right spot — which is why locating it accurately first saves so much disruption.
Some shell repairs need the pool level lowered below the crack, and a few need the pool empty. If a repair needs draining, we plan it for the dry months where possible, for the same ground-pressure reasons that make winter the right time for acid washes.
Getting the most out of the visit
A little preparation makes leak detection faster and more accurate. Do the bucket test with the pump on and again with it off, and write down how much each dropped and over how many hours. Note whether the level stops falling at a particular point — a pool that always stops dropping at the bottom of the weir mouth or the level of the light is pointing straight at the leak.
Keep the water clear and the level normal before we arrive, because dye testing needs visibility and a full pool. Tell us about any recent work on the property: new paving, a tree removed near the pool, building work or earth moving can all disturb pipes and shells. And if you have an automatic top-up, switch it off for the test period so it does not hide the loss.
The cost of leaving it
A slow leak is easy to live with and expensive to keep. Every litre that leaves the pool is replaced with fresh municipal water that needs chlorine, pH correction and stabiliser, so the chemical cost climbs as well as the water bill. The water that leaves has to go somewhere, and over months it can wash out the ground under paving or around the shell.
Finding it early usually means a smaller repair. If you have done the bucket test and the pool is losing more than the bucket, it is worth booking.
How it works
Bucket test
Confirm the pool is losing more than the bucket. Try it with the pump off as well.
Book
WhatsApp 081 577 5051 with your bucket-test result and photos of the pool and equipment.
Check equipment
Pump, filter, valve and visible pipe joints checked first.
Test the pool
Dye tests at the weir, lights, returns and cracks; plumbing isolated where the results point there.
Report and quote
Where the leak is, what the repair involves, and the price in writing.
Frequently asked questions
How do I know if my pool is leaking?
Do the bucket test: a bucket of pool water on the step, both levels marked, compared after 24 to 48 hours. If the pool drops more than the bucket, it is leaking.
How much water does a pool lose to evaporation?
It varies with heat, wind and humidity, and on hot, dry, windy Highveld days it is more than people expect. That is why the bucket test compares the pool with a bucket in the same conditions.
How much does pool leak detection cost?
Leak detection is R1,200. The repair is quoted separately once we know where the leak is and what it needs.
Where do most pool leaks happen?
At the weir, around light niches, at return fittings, through the multiport valve to waste, and in plumbing joints. Cracks in the shell are less common but do occur in older pools.
Does the pool need to be drained to find a leak?
No. Leak detection is done with the pool full. Only some repairs need the level lowered or the pool emptied.
Can a pool leak damage my house or garden?
Over time, yes. Escaping water can wash out soil under paving and around the pool shell. Wet patches that never dry are worth investigating.