Pools that leak, can leak from the underground pipes and the shell.

Your pool will naturally lose some water to evaporation, some to splash-out and some to backwash wastewater. You may also gain water from rainfall. Rule of thumb is that if you're routinely adding more than two inches of water to your pool per week, you may have a leak. It is worth spending some time and money to repair.

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.

A leak in the suction line (air in the pump) often doesn't result in loosing water!

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 using specialized electronic equipment. 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 full sun 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'.