Water Filter FAQs

  1. Reverse Osmosis History
    In 1953, Loeb and Sorirajan first prepared a high water flux (Water Flux, WF) and a high salt rejection (Salt Rejection, SR) cellulose acetate reverse osmosis membrane, thus laying the basis of reverse osmosis technology, which led to the rapid development of other membrane programs.
    In the mid-fifties, a scientist, Dr. S. Sourirajan, at the University of California, Los Angeles (UCLA) invented the "artificial imitation of biological selective membrane". This was the first time humans could use the principle of reverse osmosis. The US federal government invested in the region of 4 billion dollars in the successful research of the use of the principles of reverse osmosis on sewage pressure, so that only pure water molecules, and not harmful substances emissions, could penetrate the membrane to produce pure water.
    The first time NASA used the process was on the space shuttle, where they were able to reclaim the astronauts’ urine and sewage and then purify it for drinking. It is also used on aircraft carriers and in submarines, and for desalination for soldiers to drink, as well as being used to provide drinking water for ordinary families in the United States. This breakthrough in human drinking water and sales around the world prove its reliability.

    The first batches of reverse osmosis membranes were used in the 1950s, primarily in the desalination industry, but the cost of distillation was high. Their performance and potential was immediately discovered by the US Department of NASA and their development was funded to solve the problem of spacecraft drinking water.

    From the 1970s, the low-pressure osmotic membrane started to appear and the first batch of small household reverse osmosis drinking water purifiers also began production. These were able to purify about one to five liters of drinking water per day, and were able to effectively solve the US central and southern desert areas problems caused by nuclear radiation pollution of the water.

    Today, home reverse osmosis equipment is able to provide 285 liters (about 75 gallons) of drinking water a day, enough to meet the drinking and cooking needs of a small family or office. In addition the change in water pressure from the first generation’s high pressure down to the present 50 pounds per square inch of fifty pounds of water pressure (50PSI) makes it suitable for general use and for tap water pressure.

  2. Reverse Osmosis Principle
    In 1748 French scientists first discovered the phenomenon that water can permeate a pig’s gallbladder but, based on the production technology of the time, this knowledge could not be used in a practical way. This phenomenon was used over the next two hundred years to explain other various natural phenomena, such as the theory on how trees absorb moisture. The principle is as follows:

    If the permeate membrane separates brine on two sides with different concentrations, the water molecules will move from the low concentration side to the high concentration side in order to balance the potential energy on both sides, until the water level and water pressure difference between the two sides are equal whereby water molecules cannot be relocated and material exchange is balanced. This is the osmotic effect (Osmosis) phenomenon. Such as 4.11.
    In simple terms, in the raw water side of the application the pressure is greater than in reverse osmosis. In reverse osmosis, contaminated components concentrated in the raw water such as: dissolved and insoluble inorganic salts, heavy metals, organic matter, bacteria, and particles cannot pass through the semipermeable membrane. Only water molecules and smaller molecules of salt can penetrate the film, and flow to the water on the other side.

    To concentrate raw water the pressure has to be gradually and infinitely increased. In actual operation, if you could continue to supply raw water to maintain a constant pressure you could drain the concentrate and achieve the purpose of reverse osmosis.

    When it comes to the reverse osmosis membrane, it is included in a small part of the separation membrane. The separation membrane (CROSS-FLOW) can be subdivided into: Refer to Table 4.16.

    - Reverse Osmosis (RO)
    - Ultra Filtration (UF)
    - Microfiltration (MF)
    - GAS Separation (GS)

    In all separation membrane projects reverse osmosis membrane permeability holes are the smallest, between 0.0001 ~ 0.002 micron. For comparison the human hair has a diameter of about 10micron. You can therefore see the precision in the reverse osmosis membrane pore. In addition it effectively filters bacterial viruses and also removes toxic heavy metals in water, as shown in Figure 4.13 separation membrane application and Table 4.16 separation membrane type.
  3. Advantages of Reverse Osmosis
    The Advantages of Reverse Osmosis Method
    1. Be able to remove bacterial, virus, chemical contaminant substances from water, especially those that are difficult to treat heavy metal contaminants such as mercury, arsenic, lead ¡K etc. It lowers the possibilities of developing cancer and all chronic diseases.
    2. The water molecule group is smaller than that in the original water, easy to absorb.
    3. Impurities content low in pure and clean water, will not increase load in kidney.
    4. Good taste no odor, drinks better than common water.
    5. At the present time, the use of reverse osmosis method is recognized as the safest drinking water in the world, for home drinking of potable water, make milks, tea, medical use and prevent diseases.
  4. RO Reverse Osmosis Water Purification Process Introduction

    In general, home use RO water purification machine has two to three pre-filters (stage 1 is a 5 um filter, stage 2 is an activated carbon filter, some model has a third stage 1 um filter). For some machine, a final activated carbon filter is installed between the clean water storage tank and gooseneck faucet. The first stage filter is used to remove sediments and sand etc. particles from water. The activated carbon pre-filter is used to remove organics, odorous molecules and chlorine etc. from water. RO membrane can remove most of the dissolved impurities from water. The final activated carbon filter is used to further remove residue contaminants after RO membrane. Use the semi-permeation principle, add pressure to the feed water and force it flow through the semi-permeation membrane to the clean waterside and leave impurities at the other side and be discharged with wastewater.

    Since most of the osmosis membranes are synthetic organic materials, to protect the life of osmosis membranes, there shall be residue chlorine removal units in front of the osmosis membrane. Normally, it is accomplished through the use of activated carbon filters. And, to prevent suspended particles blockage problems, a 5 um filter is installed in front of the activated carbon filter. The pre-activated carbon filter and particle filter can remove larger particles. And, the other substances, such as heavy metals, insecticides, bacterial, virus etc. substances toxic to human bodies, and hardness and odor etc. chemical substances that can affect taste are removed by the RO membrane.

    Although RO treatment method is the complete method, among all types water purifiers, that can remove all contaminants in water, however, the area between the water storage tank and the water faucet, is the location most accessible to contamination by microorganism. Thus, some companies installed UV disinfection light to prevent bio contamination by pathogen microorganism.

  5. Reverse Osmosis Process

  6. Comparison of all types of water treatment method

    From Table 4.17 we can see that reverse osmosis method is one water treatment method that cane be used to remove contaminates.
    Table 4.17 Comparison of all types of water treatment method
  7. Water Scale Decoded(II)
    The most common filter to filter and remove scale to achieve soft water uses ion exchange resin.


    “Ion exchange "refers to: when the water flows through the filter, the resin within the material and the minerals in the water produce billions of exchanges; the ion-exchange resins are used to replace the magnesium and calcium ions found in hard water with sodium ions. When the resin is fresh, it contains sodium ions. When in contact with a solution containing magnesium and calcium ions (but a low concentration of sodium ions), the magnesium and calcium ions preferentially migrate out of solution to the active sites on the resin, and are replaced in by sodium ions. This process reaches equilibrium with a much lower concentration of magnesium and calcium ions in the solution than it started with. Its chemical formula is as follows:
    (There’s no need to memorise, the teacher will not test you)

    Strictly speaking, this type of water softener made of ionomer as a filter element should not be called "water purification equipment" because it does not remove contaminants from water. What it does is: reduces scale, removes calcium and magnesium ions from the water. However, other pollutants in the water, such as organic pollutants, microorganisms, and suspended particles cannot be filtered. So the ion resin can only be used in the front of the water purifier. It cannot be used alone to ensure the purity of water.
    In general, the life of the ionic resin is limited to about 2-3 months, (depending on the water quality conditions) before failure. Several filter kettle filters have added ion resin to remove scale, but the volumes are too small, and they usually have a shorter lifespan, so we are not very optimistic about the effectiveness of the unit’s ability to remove scale.
    Ion resin filter shortcomings. In addition to a short life and a slightly higher unit price, the other shortcoming is in the ion exchange process where sodium ions are released and which, for kidney patients, there is a health risk. A no sodium ion resin can also be chosen but water filtered in this way releases hydrogen ions and makes the water quality acidic, so the choice is the customers.
    In addition to inhibiting scale with ion resin the use of RO water purification equipment can also a good choice. The reason is that the water molecules passing through the membrane holes are only the diameter of a hair, one thousandth of the RO membrane, and will filter out heavy metal ions, organic toxins and bacteria; but the shortcomings of water obtained from reverse osmosis treatment, is that there is a discharge of waste, which is, generally, a waste of water resources.
    No matter what kind of filter water purification method used there is no 100% perfect solution. The important fact is for consumers to understand their needs and preferences, and to choose a product with a good reputation, of excellent quality and which provides the protection required of a water purifier. ALYA water purification has won the Ministry of Economic Affairs Little Giant Award, because our “made in Taiwan” water purification products have obtained excellent export results, in order for us to obtain this honor, worthy of national trust.

Water Filter Knowledge

  1. How to choose an OEM/ODM manufacturer of water purifier?
    Each trading company, brand and marketing company may develop a specific SOP for OEM manufacturer choosing.

    The following items may be the required criteria to evaluate an OEM manufacturer:
    3.Delivery time
    6.R&D capacity of new product…, etc。
    In case of the equipment damage or leakage of a water purifier caused by a poor-quality part, the seller may suffer payment or lawsuit for customer compensation. Therefore, choosing a high-quality OEM / ODM manufacturer of water purifier shall pay attention to the following additional characteristics:
    1) Private laboratory with sufficient equipment and excellent quality
    Before the trial production, a new product shall complete each test of reliability. Moreover, the following tests of reliability shall be carried out during the mass production or in case of product design change, supplier change, and so on.
    1 Cycle test
    2 Burst test
    3 Accumulation test: to simulate general user behaviors
    4 Pressure difference test
    5 Alt spray test(metal)
    6 Aging test (plastic)
    7 Tension test (plastic tube / adapter)
    8 Vibration test
    9 Drop test
    10 Power supply test
    10.1 Overload test
    10.2 Temperature test
    10.3 Electrical leakage test
    10.4 Voltage stability test
    11 Electronic components testing
    11.1 Electromagnetic wave test
    11.2 Surge safety test
    11.3 EMI / EMC protection and interference tests
    11.4 Burn-in test
    12 Water quality tests
    12.1 Residual chlorine test for active carbon
    12.2 Ion exchange resin test (Removal of heavy metal and calcium and magnesium ions (scale))
    12.3 Bacterial culture / sterilization test

    2) Global product liability insurance
    A high-quality product may have some little defect leading customer complaints. The customers’ interests will be guaranteed thanks to the global product liability insurance. However, an OEM / ODM manufacturer may not purchase the global product liability insurance because of the meager revenue in general.


    3) International certificates for each product
    Since the filtered water may be drunk, a water purifier shall be checked for hazardous substance released from the purifier body or media, expiry date and other essential factors in addition to the functions and quality. One of the demonstration methods for these essential factors is an OEM / ODM manufacturer is capable to and is willing to apply for each international and national product certificate.
    1. International product certificates:NSF, CE, RoHs and sanitary license approval documents.
  2. Water purifier recommended purchase guide
    The market for water purification products is varied. In addition to functional differences, the models appearance and their water purification technology also lead to consumers being confused. The most frequently asked questions from consumers are: Firstly, what kind of water purifier do I need for my home? Secondly, aren’t more filters better? Thirdly, can I really drink filtered water? Isn’t boiled water safer? We now want our consumers to ask questions, so we can provide them with immediate answers to assist them with their selection of water purifier (water filter).

    If you choose the water purifier based on the 5 key points below you will not waste money.

    1. You only need to drink pure water. You don’t need water with“magical effects”,
    such as those water purifiers on the market which offer many special features, such as: alkaline water, energy water, far infrared water, activated water, activated cells, enhanced immunity, etc. While these products may add more value, the additional features are usually not worth the price, If there is no specific need, buying a quality Taiwanese made water purifier will meet our daily needs for the drinking of pure water.
    2. Select features according to the regional water quality characteristics.
    For example: Although Taiwan is a beautiful treasured island which, not only has its own special scenery and cultural style, there are still noticeable differences in the water quality in different areas. In general, the water quality is better in the north than in the because of the high carbon content. Calcium is commonly known as hard water so drinking it means the taste is poor. If you buy a water purifier on the Internet please remember to choose the correct one for your area.
    (Click here for more information on water quality throughout Taiwan)

    3. Understand the function of the filter. Do not listen to the exaggerated words from companies.
    Each of the different materials in the filter has its own importance. For example, the PP filter can remove sediment (including larger sediment) and other impurities from the water. Hollow fiber membranes can filter out most bacteria, and RO reverse osmosis filters can filter out more small viruses. It is recommended that consumers do their homework by first reading this article: "water filter core comparison function table"

    4. With filters having standard specifications the purchase and installation in easy.
    Almost every water purifier manufacturer uses a dedicated filter connector for quick and easy installation, to prevent leakage, and which is suitable for people to use on a daily basis without the need to spend a lot of time studying the filter area to replace it.
    The benefits of a general specification is that it is easy for Carrefour and other large buyers to buy filters. However, the product may be of poor quality, may have assembly problems, and could leak. We suggest that you only purchase well-known domestic brand.
    5. Regular replacement of the filter is better than purchasing a high-priced water purifier.
    The purpose of the filter is to filter the harmful substances in the water, which, through long-term use, clog the pores and cause other issues. We often hear from a friend or a consumer who has forgotten to regularly replace the filter because of their busy life and who only does so when the flow of the water is reduced or when the water starts smelling. Many appear shocked when they realise they haven’t changed the filter for over a year. In these situations the residual bacteria in the filter may be far greater than in ordinary water. The amount of bacteria in high priced, high-standard water products may cause more harm than drinking water directly. You do not want to drink water with bacteria in it. Therefore, water friends, please remember to regularly replace the filter!


    The above shows the most common combinations on the market. However, there many manufacturers have also introduced small water purifier products with a multi-material combination single filter. Make sure you have in-depth understanding of each filter material so you can make the best choice for the most suitable filter for your own water purifier.
    Can you really drink purified water?
    The problem with drinking water is not how much bacteria is in it but how much chlorine has been added by the Taiwan Water Company to reduce levels of bacteria. In principle water from the water plant is in line with the standards. However, the pipelines in most areas of Taiwan are old and households use water towers for storage of water. Bacteria breeds in the pipeline and water towers meaning that most of the water cannot be drunk in its raw state. Bacteria consumed through the drinking of raw water can easily lead to diarrhea and sickness.

    In addition to bacteria, there is another harmful microbial – virus that is about 20-200nm in size; much smaller than the bacteria, which is 1,000-10,000nm in size. As RO reverse osmosis membrane pore sizes are less than 1nm, viruses and bacteria can be completely blocked so the water is safe to drink.
    Taiwanese poison authority Xia Jue Lin has given 10 major pieces of advice regarding food safety, one of which is the suggestion that homes should install a RO reverse osmosis water purifier, to avoid drinking water from water stations.

    Choose Counter Top, Under Sink, or Tap Water Filer
    Regardless of the form of the water purifier filtering is still a major consideration. The more specialised item is the tap water purifier. Due to its small size the amount of water that can be filtered is less. However, the price is cheap, and it is easy to install, especially for students living away from home or for our single friends to use.

  3. General Knoledge of RO System
    Every time when we visit the water purifier shop, seller introduces the product with technical terms which really confuse us.

    “RO” was named from the former two letters of Reverse Osmosis; full name is Reverse Osmosis water purifier. This system is normally as be called “RO system”.

    At present, RO system is still one kind of best-selling, the safest household used water filter all over the world.


  4. Why do we call “PP” cartridge? – General Knowledge
    We always hear sales person called 1st stage filter “PP cartridge”. Why do they call it PP?

    1. Source of information
    PP cartridge is made from Polypropylene material which micro-fiber will be melted and spun into a cylinder type. We usually use word “melt-blown” to describe this type of cartridge.
    2. Inventor
    The 1st company invented “PP cartridge” was 『Osmonic co.,』 in USA. This type of cartridge is less expensive than string wound cartridge. The process of “PP cartridge” is quicker and cheaper. For these reasons PP cartridges are most common so far.
    3. Function:
    PP cartridge can remove substance or particle from water. Normally PP cartridge will be installed as 1ststage in water filter.

    4. Microns:
    When you ask sales person『What the micron PP cartridge does?』 the sales people usually answered 1 micron, 5 or 10 microns.
    And it takes more cost and higher technology to produce 1 micron PP cartridge. Of course, the function of 1 micron PP cartridge will be better, too.
  5. Using APP to check water quality at home
    When you step inside the hypermarket and stand in front of water filter selling area the salesman always introduces you the most expansive water filters and try to convince you to purchase those filters. They intend to brainwash and give you an idea of “the more expansive the better”. Surely, the salesman promotes the high-cost water filters to consumers as they have to pay astronomical of slotting fee to hypermarket day by day. Even worse the salesman will try to add ALL the expenses to products if they cannot sell any products within a week.
    It will be so kind of you showing your understanding and sympathy to salesman if there is no harm for you to purchase products not worth to its value.
    Nowadays, this bull campaign situation is held in contempt in some water filter suppliers. Hence, a free APP was revealed and ones can check their home water quality easily. Even better that this APP is able to recommend you the most suitable water filter for your use. No extra fee will be charged.


    Using this APP you can be an expert when choosing water filters.
  6. Health and Life
    Modern people understand to take care of their health, health will be superior to either eating or using, but you know ? It is possible for the water you use to be the factor which causes your body unhealthy.
    Everybody knows it is healthy to drink after filtration, how about bath water? Tap water consists of chlorine, and chlorine generates “Trihalomethanes”.
    What is Trihalomethanes? Trihalomethanes was generated from tap water factory, then what damage will it cause to our health ?
    According to the study of Trihalomethanes, it maybe carcinogenic, causing serious damage to body.
    How can Trihalomethanes enters to body to affect health ? About 80% of them will enter by the respiratory tract, and the following 20% will enter by skin contact.
    So this is the reason why everybody always says that it is not necessary to take a bath too long, for the rest 20%, if it should be avoid?
    The water which modern people drink all choose water filters to filter, if bath water is need to be filtered !! Don’t let our bodies to be unhappy.
  7. Would Water without Minerals Affect Health?

    Through RO technology, pure water machine removes bacterial, virus, scales etc. contaminants from water and produces fresh, sweet and drinkable water. However, at the same time, it removes many minerals from water. Another point to make is that, drink pure and clean water for a long period of time, although it is not hazardous to human body, it also reduces the body intake of minerals, not beneficial to health.

    Another view is that, specialists consider that the purpose of drink water is to supplement water. There should be extra requirement for water. The minerals and nutrients required by human body should be supplemented by food. For example, doctors would never let people deficient in calcium to drink water with high scale. Their recommendation is to use calcium tablets or drink milk. And at the present time, there is no technology in the world that can guarantee to remove contaminants hazardous to human body from water and, at the same time, preserve substances that are beneficial to human body. Thus, we have option to ingest nutrients from food. And, we cannot select the drinking of dirty water and lead to slow hazards to human body. Thus, for health and safety, it is better to drink pure and clean water.

    Both sides have reasonable arguments, we cannot make conclusion as yet. The consumers shall make selection in accordance to personal conditions. However, we can have a peace of mind that for those users that have installed water purifiers in home, there is one user has used for more than 8 years. No loose of hair and teeth conditions developed as yet.

  8. People who drinks from Reverse Osmosis System would suffer from Osteomalacia?

    This is a misunderstanding. The food that people consume in daily life has much more minerals even compared with the ones in a small pool.

    According to American Medical Journal, people get the minerals mostly from daily meals instead of water. Therefore, you don’t need to worry about suffering from Osteomalacia if you consume the water through RO System.

    In addition, currently there is not a water treatment technology that could preserve the beneficial minerals but filter all the hazardous substances. Hence, it is recommend filter all the elements out from the water and consume the minerals from food and fruit.

    After the water filters from the Reverse Osmosis System, the TDS* would decrease to around 30-50 ppm. (The salt rejection of RO machines is around 94%. As per the TDS in Kaohsiung Taiwan is 500 ppm, after the water source filtered from the RO membrane, the TDS would decrease to 30 ppm.)

    (If you need to learn more about the water quality analysis in Taipei City, please visit us at https://goo.go/eD3b4r . If the filtered water in Taipei is close to pure water, does it mean that the civilians there would suffer from Osteomalacia?

    Easywell has committed to produce RO Systems, water filters for home and industrial uses in Taiwan since 1986. We insist to use RO membrane technology to remove hazardous compounds and give you the purist water.

  9. How to select the right Sediment Filter?
    Sediment PP cartridges are the basic filters which can remove small particle such as sand, mud, asbestos, silt, and turbidity from the water. They are made from melt brown PP fibers.

    Normally speaking, sediment PP cartridges are used to remove all types of sedimentary particles as per the required micron rating. PP pore sizes are divided to 1 micron, 5 micron, 10 micron and 20 micron.
    These materials are cheaper compared to the materials used with other cartridges and it is where sediment PP cartridges got its other name of low-cost infiltration cartridges. Also, PP cartridges prevent pressure difference during the filtration. These materials are rather preservative, safe, and inexpensive and have good filtering rates. Sediments PP cartridges are equipped for the first stage cartridge in water filters and RO systems.

    There are three types of PP cartridges which are melt blown, wound filter and pleated filter. Although the melt blown cartridges’ filtering rate and service life are lower compared to other PP filters and it is the cheapest one among their kinds. Melt blown filter is also the standard one in water filters in the market.
    On the contrary, the pleated filter has the best filtering rate but has the most expensive price. Furthermore, the wound filter has both high quality filtering rate and competitive price.

    In addition, it is recommended to replace the PP cartridges once in 2-3 months. After using these materials for 2-3 months, you could find them discolor due to the sediments and rust. Although PP’s price is quite affordable, people should be avoided purchasing bad quality products.
    If the production process is poor, this would cause the pore size too big. Plus, poor production would lead the PP to deform once contacting with high water pressure. Above situations would certainly affect the filtering rate. At result, the sediments might flow to the following filters and result in clogging.

    It is suggested that you press the sediments PP cartridges to check if it is firm before purchasing. Also, you could buy from ALYA which has released high quality filtering materials to bring you clean and safe pure water.
  10. How to prevent Legionnaires' disease in drinking water?
    In recent days the media has reported on two infants suffering physical discomfort from the contraction of Legionnaires' disease. Fortunately these two young children were able to return to full health.


    First, what is "Legionnaires' disease" ?
    (Original News http://news.ltn.com.tw/news/life/paper/800073)
    Legionnaires' disease is caused by many different types of " Legionella bacteria "
    The main route of transmission and infection is through inhalation, breathing in Legionella through water vapour or droplets;
    Symptoms often include: fever, cough, headache, abdominal pain, anorexia, etc., which can lead to pneumonia,

    In an infected adult, if not treated in time, it can lead to respiratory failure and death. ; The mortality rate for adults who are infected in 15%.

    Very few children are infected and the two babies referred to above are said to the world's youngest reported cases. The Legionella bacteria prefers a water environment, especially a warm environment (25 ° to 45 ° C, although the most suitable temperature is around 35 ° C), therefore, regular cleaning of water towers, open drink machines, drinking fountains and other facilities is very important!

    The two babies were infected because the cold water in the water dispenser was contaminated, and they accidentally inhaled the bacteria into their lungs through drinking milk.

    So, parents, please pay special attention to the home drinking water system (from the water tower through to water pipes and water purifiers, drinking fountains, etc.) and that they are cleaned.

    According to the suggestions on Wikipedia's, legionella can be eliminated through the following action:
    1. Temperature sterilization: water should be heated to at least 70 ° C and this temperature should be maintained for three minutes.
    2. UV sterilization: exposure to ultraviolet light, wavelength 254 nm can make bacteria inactive.
    3. membrane technology: There is now more and more use of membranes to remove microorganisms. Particles with a diameter of less than 0.2 micrometers can be generally used to ensure bacteria, and even some viruses, are filtered out.
Switch The Language