Why Should I Bother with a Pre-Filter?
Although many homeowners do use ionisers without a pre-filtration system, doing so can create health risks and also be damaging to the ionizer. The cleanliness of water coming into the home varies throughout the United States, so in some areas, the mains supply will be affected by contaminants that a regular ionizer filter cannot deal with.
Hard water is of exceptional concern because it can clog up the working parts of an ionizer. As it’s such a common issue, many manufacturers void their warranty for units which have been damaged in this way.
Not everyone uses a pre-filter in conjunction with their ionizer, but it undoubtedly has advantages. One of the most pressing concerns people have is the addition of fluoride to the mains supply by many authorities across the US. Pre-filters can eradicate the majority of this chemical, and produce a much better tasting liquid as a result. Pre-filters can also make water smell better in areas where hydrogen sulphides are present in amounts significant enough to cause an unpleasant odour. If you have an ionizer, but the water still retains an odour after passing through, a pre-filter may be the answer.
If you’re undecided about getting a pre-filter because you don’t currently have a problem with taste, smell or fluoride, then it’s worth bearing in mind another key benefit – they can keep your ionizer working optimally for longer. This is because the number of particles in the water which passes through the unit is reduced. Therefore, less build up occurs and the internal filters are under less strain.
Remember, pre-filters can be bought to minimise the presence of bacteria, heavy metals, unpleasant smells or tastes, and various chemicals, but they do not take out any mineral content. Here’s a look at the most popular pre-filters on the market, and an explanation of how they work.
Ion Exchange Filters Explained
Using an ion exchange filter you can rid your aqua of various pollutants, this is accomplished by exchanging them with another, non-toxic substance. During the process, both the new substance and the pollutant are dissolved. When impurities are dissolved into the water they can form ions - the parts of a material which have electrically charged properties. In natural water, the quantities of negatively charged ions and positively charged ones are relatively similar.
As the process gets underway inside the filter, the liquid moves through beads known as ion exchange resins. In doing so any unwanted ions in the water are exchanged with ions attached to the beads. Two of the best ion exchange techniques are deionization and softening.
Softening can cut down on the hardness of the water. Softeners have beads which replace single magnesium and calcium ions with two sodium ions. De-ionization works slightly differently, here the beads are designed to swap hydroxyl ions for anions or hydrogen ions for cations. As a result, the cation beads release contaminants like sodium, lead or calcium with a positive charge. While the anion beads release contaminants like sulphates, chloride and fluoride, which have a negative charge.
Ion exchange filters can only work on crystal clear water which contains dissolved elements. If the water is discoloured or has a cloudy appearance, it’s likely that some of the contaminants have not broken down and remain in a solid form. These types of the larger fragment cannot be removed using an ion filter and will instead clog up the unit.
Using a PP Fibre Filter
PP or polypropylene fibre filters are adept at taking away fragments of silt, asbestos and mud from a liquid, ensuring that even water which has been churned over becomes crystal clear. You can buy PP fibre filters that are appropriate for the volume of water you need to process and the type of particles that are present in the raw supply.
Surface filters are so-named because they trap pollutants on their surface, which eventually becomes full and will need to be either cleaned or replaced. These can work well when filtering out contaminants of a similar size.
Alternatively, if you need to remove particles of differing sizes, a depth filter could be more efficient, as they are designed to capture larger elements on the surface and then smaller elements in their core. The fluid filters through its outer shell, entering the inner core where the liquid is sieved through numerous layers of polyester-type fibres, some of which are pleated to increase the area used to capture particles.
All PP fibre pre-filters are classified by micron units, which are equivalent to one-thousandth of a millimetre. A lower micron count means the filter can remove very small elements, but you also need to be aware of the terms ‘nominal’ and ‘absolute’, as these indicate the reliability of a filter. A five-micron filter described as nominal is able to trap up to 85% of particles that are five microns or bigger, if a five-micron filter is described as absolute, you can expect it to trap up to 99.9% of the same sized particles. Some people go for a nominal filter for general use, but to attain the best quality drinking water, a filter rated as absolute is vital.
As production costs are small and the materials used are not expensive, PP fibre filters have a low initial cost. Spun filters are the cheapest of all, but pleated filters are not especially costly either. In the long run, it is pleated filters which represent the best deal, as this type of cartridge can be washed and reused whenever necessary.
How do KDF Filters Work?
A KDF or Kinetic Degradation Fluxion filter uses a copper and zinc-based formula to set off a chemical reaction known as redox. During this process, electrons are swapped for contaminants, transforming potentially harmful elements like lead, mercury, or chlorine, into less toxic or completely nontoxic substances.
Alongside the removal of unwanted chemicals and minerals, KDF pre-filters are highly effective when it comes to destroying microbial life. They do this in one of two ways; either by establishing an electrical field in which microbes cannot live or by inhibiting their ability to function normally by forming peroxides and hydroxyls.
If you have a carbon filter, a KDF pre-filter may also help to keep your unit functioning for longer. This is because KDF filters cut back on the build-up of chlorine which can occur, enabling the carbon filter to be more effective.
Which Pre-Filter is Right for You?
Pre-filters are on offer from many suppliers but there are different systems which tackle specific problems, so selecting the right one for your needs can be confusing. If you are unsure of what specific problems affect the H2O in your area, you can either browse the Environmental Protection Agency report for where you live or have a sample of your aqua professionally analyzed to find out more.