Spa's and swimming pools need to be regularly maintained and most of this maintenance involves water treatment and testing devices as well as other equipment.  There are many different variables that need testing for and are therefore numerous types of equipment on the market to help with this.

One thing that you may test for when maintaining your pool or spa, would be oxidation reduction potential.  ORP meters are available to measure this to oxidise contaminants.  ORP meters will help to monitor as well as control water suitability in a commercial or domestic swimming pool.  ORP meters are available in a variety of forms, including a bench meter.  Waterproof, portable ORP Meters are the most suitable for testing swimming pools and spas.  There are several handheld, waterproof ORP meters to choose from and they vary greatly in price.

Instruments that test for pH levels are very popular for all kinds of water testing applications.  pH meters are used regularly within the pool and spa maintenance industry.  pH meters give a precise measurement of pH values present within a sample of water / liquid.  Most Ph meters that are used to test pools are handheld probes which generally cost a couple of hundred pounds.  There are more expensive probes which test for pH but these tend to be stationary bench models.

A more sophisticated piece of machinery which is also manufactured specifically for testing swimming pools is the DCW Controller.  The DCW controller tests for chlorine levels, pH and temperature of the water tested.  The DCW controller can be used for all kinds of swimming pool and spa water treatment.  pH and water temperature can be tested accurately and chlorine levels can be controlled as well as continually measured using this device.  Chlorine control and testing is important when dealing with swimming pools as levels need to be maintained at a safe level.  The DCW controller is suitable for beginner's use but is more expensive than individual meters such as pH or ORP.

Water Treatment Devices available for purchase

All of the above instruments are available for purchase from online suppliers of water treatment devices.