general information

Reverse osmosis (RO) systems ideally are plumbed into soft water feeds for high purity filtering and scale-free kettles, for the removal of chlorine, sodium, fluoride, nitrates, nitrites, cryptosporidium, heavy metals, pesticides, colour, odour, taste, etc. Reverse osmosis filters last twice as long on soft water and booster pumps are less likely to fail prematurely.

Single carbon filters are not as effective as reverse osmosis systems as they are fed off hard water and leave the water hard. They will remove chlorine, colour, odour, taste, pesticides, grit and sediment. Carbon filters range from 0.2 to 10 microns, compared to the end of a human hair being 70 microns thick. Reverse osmosis systems usually include three carbon filters.

The recommendations for chlorine concentrations in drinking water are between 0.1 to 0.2 ppm to sterilise bacteria. Excessive chlorine is easily detectable and can be filtered out prior to drinking for a better taste. Water schemes are monitored by sanitary authorities for bacteria, but additional filtering at household level may often be required.

E.coli indicates the potential risk of other more harmful organisms in water and safe limits may be exceeded after flooding.  Micro-organisms range from below 0.1 microns to over 10 microns. Most types can be blocked by 0.5 sub-micron filters (Doulton ceramic) or reverse osmosis systems along with ultra-violet sterilisation.

Water is classed by the EPA as being soft below 50 ppm of lime and hard at over 200 ppm causing damage to pipework. Many water schemes are extremely hard at around 400 ppm. Water softeners will soften hard water to below 5ppm, a tenth of the Environmental Protection Agency softness classification.

With soft water, Calgon and scale cleaners are no longer required. Shampoo, powders, detergents and soap form full lathers.  Clothes will feel softer and gain higher durability. Skin feels much softer and itches less often. The low running costs of salt will be easily met by the savings made on cleaning products.

Heating of hard water causes lime to solidify, but existing scale in showers, dishwashers, washing machines, irons, heating elements and pipes will be dissolved by soft water, eliminating further damage or heat loss.  Immersions and heating coils will return back to full efficiency if previously scaled by lime.

For softeners, tablet type salt should be used, preferably Axal Pro or Broxo salt.  Salt can be bought from hardware stores for around 7 euros per 25kg bag. Normal household use is one bag every 4 to 8 weeks.  Don’t use fine salt granules, as they can clog up salt bins and block brine siphons.  Always keep salt topped up.

Sodium stays below EU limits, in water softened from hard water with 400 ppm lime and trace sodium. Laboratories can provide sodium tests for peace of mind or a reverse osmosis filter system will guarantee sodium levels to a 1/20th of the level of the strictest EU limits. The sodium in softened water is also 1/20th the level of most brands of supermarket soup.