Diagnose a suspected pool leak using the bucket test, dye testing, and pressure testing of buried lines

Steps

1. Run the bucket test first to distinguish evaporation from an actual leak: place a water-filled bucket on a step, mark both the bucket's and pool's water levels, and compare drop after 24 hours
2. Check obvious above-water sources first (equipment pad fittings, pump seals, heater, visible cracks) before assuming the leak is in buried plumbing or the shell, since equipment-side leaks are cheaper to fix
3. Use dye testing at suspected structural points (light niches, fittings, cracks, skimmer throat, steps) by releasing dye near the suspicious area in still water and watching for it being pulled into a gap
4. Pressure test buried suction and return lines individually, isolating each line, pressurizing, and monitoring for pressure loss, to localize a plumbing leak before excavating
5. Narrow down further with a listening device or electronic leak detection equipment along the suspected line route if pressure testing confirms a specific line is losing pressure
6. Confirm the leak location before recommending excavation or repair, since digging based on a guess rather than a confirmed test result is a common source of wasted cost