Reverse Osmosis
The semi-permeable membrane used in reverse osmosis contains tiny pores through which water can flow. The small pores of this membrane are restrictive to organic compounds such as salt and other natural minerals, which generally have a larger molecular composition than water.
Pros
Coway
The semi-permeable membrane used in reverse osmosis contains tiny pores through which water can flow. The small pores of this membrane are restrictive to organic compounds such as salt and other natural minerals, which generally have a larger molecular composition than water.
Pros
- The membrane pores are restrictive to bacteria and disease-causing pathogens to avoid waterborne diseases.
- Can filter/ reduce
- Radioactive substances like radium and uranium,
- Heavy metals such as mercury, cadmium, arsenic, chromium, and lead
- Microbes; virus and bacteria, etc.
- Nitrate, fluoride
- Incredibly effective at desalinating water and providing mineral-free water for use in photo or print shops.
- The small pores in the membrane is unable to block more dangerous chemicals like pesticides, herbicides, and chlorine which are molecularly smaller than water (Binnie et al, 2002). For this reason, a carbon filter must be used as a complimentary measure to provide safe drinking water from the reverse osmosis process. Such chemicals are the major contaminants of drinking water after municipal treatment.
- The removal of healthy, naturally occurring minerals in water. The membrane of a reverse osmosis system is impermeable to natural trace minerals. These minerals not only provide a good taste to water, but they also serve a vital function in the body’s system. Water, when stripped of these trace minerals, can actually be unhealthy for the body. HEALTH RISKS FROM DRINKING DEMINERALISED WATER by World Health Organization (WHO)
- Reverse osmosis also wastes a large portion of the water that runs through its system. It generally wastes two to three gallons of water for every gallon of purified water it produces. Reverse osmosis is also an incredibly slow process when compared to other water treatment alternatives.
- The are some precautions on drinking RO water though:
1) Don't fill RO water in plastic bottle because of leaching effect. It's best to fill RO water in glass or stainless steel bottle.
2) It's not recommended to drink RO water immediately after exercise. Isotonic drinks like 100plus can replenish the salt lost through sweat.
3) Maintain a healthy diet or take nutrient supplements if you're to drink RO water.
Coway
Source: penapiscoway.com. |
Elken Bio Pure
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REVIEWS | |
https://forum.lowyat.net/topic/2548124/all 2012-2016 Using Elken for 11 years. No problem. Just need to change the filter every year during our CNY clean-up. Elken is by far the best, but costliest too in terms of maintenance. R.O. home water treatment are not cheap. In fact, pretty expensive. So I see no point in using such system when other systems which does not remove minerals exist. Coway bestest. After sales maintenance service toppest I agree that RO system is not cheap. Chemicals are generally categorized into organic chemical or inorganic chemical. To know which chemical is organic or inorganic, you can Google the name of the chemical and if the chemical structure has a carbon atom or 'C' in it, then it's an organic chemical. Most of the system in the market I've seen which allow good minerals to bypass are activated carbon filter. Organic contaminants contain carbon molecules which can bond to the activated carbon filter. A well designed activated carbon filter can filter organic chemicals and some inorganic chemical such as chlorine, lead and mercury. The disadvantage of activated carbon filter is it's not effective in removing most inorganic contaminants such as arsenic, nitrate, or heavy metals like chromium and cadmium. RO membrane can filter these inorganic contaminants. Most RO system also have pre- and post-activated carbon filter to filter organic contaminants. So a well designed RO system can filter both organic and inorganic contaminants. There is no filter in the market which can differentiate between good minerals and bad minerals. This is a marketing gimmick. If the filter can retain good minerals in the water, chances are it also retains other inorganic chemicals in the water. I do not deny the fact that some minerals in the water are essential to our health such as calcium and magnesium. Individuals who does not maintain a healthy diet can benefit from the calcium and magnesium content in the water to prevent certain illnesses. For those who drink RO water, the lack of minerals in the water can be supplemented from food intake. Between a choice of drinking filtered water containing good minerals plus inorganic contaminants, or RO water which doesn't contain organic and inorganic contaminants while lacking good minerals, I personally choose RO water and supplement the minerals from food and nutrient supplement intake. A glass of milk contains more calcium than a glass of water. Don't use any marketed brand. Water systems are simple and the technology is cheap and easily available. Just go to a water filter place. They usually have cheap, custom assembled RO systems. Tell them what you want an they will quote you. You can buy the filters anywhere. |
Ref: historyofwaterfilters.com, Lowyat.net, aquaclearllc.com, nutritiondata.self.com,