Understanding Pure Water

MYTHBUSTER (in techtalk) : You DO NOT need TDS ‘000’ for a spot-free finish.

We have tested ePLUSensively with window-cleaners and retailers to prove this point.  Our tests demonstrate that the ‘spot’ left by a TDS of 50 and below is invisible.


With this in mind, PureH2O systems are designed to give you the control of the TDS output of your system, and therefore the flexibility to save $.


That said, ALL PureH2O Systems are designed to give you TDS 000 when you choose !


Understanding Pure Water


TDS : TDS stands for ‘Total Dissolved Solids’.  As pure water evaporates spot-free, any mark left on the glass when the water dries, is caused by the solids that were ‘dissolved’ in that water.  So .. the TDS measures the amount of solids in the water, or in practical terms, the size of the spot once the water dries.


UK SYSTEMS : Pure Water for window cleaning was ‘discovered’ by Ionics in the UK.  There, the water ranges from TDS 200 - 500.  The marks left by their tap water (similar to Perth) are intolerable both commercially or domestically.  The Ionics Systems are made in the UK mostly for these water conditions.  The reality is that Australian water is so much better, that their systems are over-engineered for our conditions.  Starting at TDS 80, we only need to remove half the TDS to get a Spot-Free finish.


SPOT-FREE : The Human Eye cannot see the spot left by TDS 50.  This is easily proved.  So ... getting the result below 50 will deliver a Spot-Free finish.  In Sydney and Melbourne, with Tap Water now at TDS 80 and below (thanks to De-Salination plants etc), the use of Pure Water is not even necessary on many sites.  Many Australian Window Cleaners are using Tap Water and Reach-IT poles without even a Se-Ca-DI.


TDS ‘000’ : TDS 000 means all the minerals have been removed from the water.  This leaves the water in a different configuration to any other water.  At TDS 000, water becomes an aggressive cleaning agent - desperate for something to be dissolved in it !  You see .. water wants to be dirty ... to get an idea, stir a teaspoon of fine dirt into a cup of coffee, and you will see the power of water to take solids into solution.  So ... this means that, even the Tap Water style window cleaners in Sydney and Melbourne can benefit from a Se-Ca-DI Pure Water System - there is always a time when you will need Pure Water.


WINDOW CLEANING EXPLAINED : Window Cleaning (regular) involves only 2 steps - Agitation, and Removal.  Traditionally, we agititate with an Applicator - this ‘stirs’ (dissolves) the dirt (solids) into solution.  Then we remove the dirty water with a squeegee, working from the top edge down.  The detergent has little to do with the cleaning process (other than greasy finger prints) .. it is really in the water as a surfactant to enable the squeegee rubber to glide over the glass.  Cleaning with Pure Water is exactly the same but with different tools.  The brush bristles do the job of the applicator and ‘stir’ the dirt into solution, while the jets of the brush do the job of the squeegee, starting at the top, working the dirty water off the glass.  Done properly, all the dirty water is ‘chased’ off the glass, leaving only spot-free water to dry.  As with the squeegee, if you miss any of the dirty water, it will dry leaving the dissolved solids on the glass.

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