Crawchy’s Swim School


Crawchy’s Swim School (CSS) was established in 2012 and is a purpose built indoor learn to swim pool based in Helensburgh, NSW. Within just 18months of opening, CSS grew rapidly and is now the preferred Swim School within Helenburgh. However, it was found that the traditional methods of water treatment were insufficient with the increase in bather load. Subsequently, CSS contacted Ozone1 to help improve both water quality and bather comfort. Within hours astounding results were achieved with chloramines dropping from 2.5ppm to 0.3ppm!


Only hours after commissioning Ozone1’s “Total Solution”, the water clarity and odour improved dramatically, Primary Disinfection levels stabilised and combined chlorine decreased by 2.2ppm.

Pre Ozone 1 Post Ozone 1
Combined Chlorine 2.5 ppm 0.3 ppm
Free Chlorine 3.5 ppm 2.0 ppm
Total Chlorine 6.0 ppm 2.3 ppm
pH 7.4 7.2


Secondary Disinfection: Ozone1’s Proprietary System Calculation was utilised along with our unique Advanced Oxidation Process (AOP) as a secondary disinfection system, which was suitable to combating CSS’s combined chlorine and in particular the monochlorinamines issues.

Primary Disinfection: Ozone1’s Hydroguard -302 Blue I DPD1 & DPD3 controller was utilised to ensure consistent levels of Primary Sanitation (Free Chlorine & pH).

The Hydroguard Blue I controllers uses a colorimetric DPD method to determine the Free Chlorine & Total Chlorine measurements as opposed to relying on traditional ORP or Free Chlorine sensors. As a result, the outcome is extremely consistent sanitation (Chorine & pH) levels. The ‘Blue I‘ conducts a DPD1 & DPD3 test every ten minutes, and each and every test is uploaded via our “Remote Monitoring” to the Cloud and is stored for 2 years, which serves as valuable evidence to satisfy a possible complaint. The remote monitoring also allows CSS to access and view their water quality at all times and if set points aren’t met, alerts are sent to the appropriate personnel via text message or email.

Crawchy’s Swim School pre Ozone1 Install
Pool Category Indoor Learn to Swim School
Pool Volume 53,000 Litres
Primary Disinfection RolaChem 9 – Automatic Acid (pH) & Chlorine (ORP)
Secondary None
Temperature 32 degrees Celsius
Bather load 650 per week