Salt water purification systems for spas and hot tubs are now generally available but what do you need to know about them?
Salt water pools have become increasingly popular and now salt water systems are available for your spa.
Salt water purification systems produce chlorine or bromine from salt by electrolysis. They have been used in swimming pools for many years and are becoming increasingly popular.
The same technology has now been applied to spas and hot tubs.
Salt systems have several benefits including ‘smoother’ softer feeling water in your spa.
They tend to produce far less chloramines – and it is the chloramines that give that ‘chlorine smell’ to either pool or spa water.
Many people find the water less likely to irritate your skin or your eyes.
Salt water systems are gentler on hair, even if it is dyed or blonde.
The running costs can be lower that traditional systems and there are ecological benefits.
All water treatment methods have their pros and cons, but there is certainly a lot to be said for a salt-water spa.
How does a salt water spa system work?
First of all, salt, in form of sodium chloride or sodium bromide is added to the water. The former will generate chlorine while the latter will produce bromine; both act as sanitisers.
Bromine is less affected by the higher temperatures in a hot tub and is more effective over a wider range of pH values than chlorine.
The amount of either salt added is very little. For instance the sea has a salinity of about 35,000 ppm, our own salty tears are roughly 9,000 ppm but a salt-water spa system will run at about 2,500 ppm, below your ability to taste saltiness.
These low levels also mean that the water is safe for the spa itself and won’t cause corrosion in any metal parts or fittings.
The treated water passes through a low-voltage, electrolysis cell, which releases the bromine which, in turn, sanitisers the water.
Under certain conditions – perhaps after an especially high bather load – the spa may need to be shocked by traditional methods but a well maintained salt water spa should only need it’s water replacing once or twice a year which means that money will be saved on energy bills from re-heating the fresh water as well as reduced chemical costs.