Browse Green Pool and Algae articles, guides and tips on the Pool Care Australia blog.
Fixing a green pool in Australia typically costs between $150 and $800. Light algae runs $345–$500, a fully green pool hits $500–$720, and a swamp pool can reach $920. DIY chemicals cost $67–$133, but test kits, protective gear, and repeat treatments push that higher.
Heavy rain turns your pool green fast. It dilutes chlorine by up to 30% and drops pH below the safe 7.2–7.6 range, creating ideal conditions for algae to bloom within 24–48 hours. Rainwater sits around pH 5.6, which destabilises alkalinity and accelerates chlorine loss.
Green pools turn cloudy and murky within 24–48 hours when chlorine drops below 1 ppm. Black spot algae looks completely different—tight, dark circles of 1–3 cm with sharp edges, rooted up to 2 mm into plaster. Green pools respond to shock treatment and algaecide.
To shock a green pool in Australia, test your water first and balance pH to 7.2–7.4 and alkalinity to 80–120 ppm. Calculate your pool volume in litres using length × width × average depth × 1,000. Light green pools need 7–10 ppm of shock; dark green needs 30 ppm or more.
Your pool turns green when chlorine drops below 1 ppm, but algae isn't always the only cause. Heavy rain dilutes sanitiser and spikes phosphate levels, feeding algae within 24–48 hours. Filters older than seven years lose efficiency, reducing chlorine effectiveness by up to 30%.