An excessive water bill and excessive use of pool chemicals are indicative of a leak. Water loss due to evaporation will vary from pool to pool.
To check whether your pool is leaking (or not): partly fill a bucket with water and mark the water level. Place the bucket on the top step of the pool. Also mark the level in the pool. The water in the bucket will be the same temperature, affected by the same natural elements, including rainfall, as the water in the pool. Note the water loss, both in the bucket and pool after a couple of days. Any additional loss in the pool can be attributed to a pool leak.
To determine whether the leak is a static leak or pressure leak: run the filtering system for say eight hours, and measure the water loss. Then, over a similar period, don't run the filtering system and again measure the water loss. If you lose water more rapidly when the filtering system is running then you have a pressure leak.
Pools can leak through the pump or filter (easy to spot), plumbing lines, skimmer-box or the pool shell itself. Pool-lights, tile grouting, main-drains and hydrostatic valves also are areas of concern.
A plumbing leak can be in the suction line (air leak) or return line (pressure leak). With pressure leaks, water is lost more rapidly when the pump is running. The leak also can be in the pump or filter.
A leak in the suction line (air in the pump, kreepy krawly doesn't work) often doesn't result in loosing water! With older pools, the leak is often under the skimmer-box.
In combination with pressure testing, using electronic equipment, plumbing leaks can be located under soil, paving and concrete slabs, thus avoiding 'digging-up half the garden'. Plumbing leaks can be tricky to repair, the main problem being access.
Finding and fixing leaks in fibreglass shells usually is easy. Letting the level drop to find the leak can be dangerous practice as the pressure of the soil can push in the walls of the pool! Although rare, very old fibreglass shells can have 'pin prick leaks'. Leaks can be easily repaired under water.
Concrete pools can leak through the grouting of the tile line. This is a common problem with old pools where the concrete decking rests on the concrete shell. Such pools are common in City Beach and surrounding suburbs. Leaks can be repaired easily under water.
With respect to vinyl liners, letting the level drop to find the leak is a no-no. Vinyl, when exposed to air will shrink, and the liner can pull itself out of the plastic beading strip, or will split. Liner pools with the beading strip below the level of the water can loose water through seepage at the strip. Sealing with silicon or epoxy is required. Well maintained, very old liners can have many 'pin pricks'.
Finding leaks in vinyl liners requires careful inspection of the liner, using electronic equipment, or diving gear and a syringe with dye. Multiple leaks are common. Leaks can be repaired under water.
Finding leaks in concrete spas can be very difficult (time consuming). The main problem is that, with exceptions, air-blower lines and Venturi-return-lines can't be pressure-tested. To facilitate finding leak(s) in spas, owners should carry out certain tests beforehand. Please ring for advice.
Leak Detectives does not attend to acrylic spas or fibreglass spas.
With specific exceptions Leak Detectives guarantees to find the leak(s). There is no charge if Leak Detectives cannot locate the leak(s). In the case of underground plumbing leaks, if Leak Detectives is found to be wrong in locating the leaks, Leak Detectives will return the paid charges.