- Foreword: Is a household water purifier necessary?
- Which brand of household water purifier is good?
- A Brief introduction to the characteristics of the household water filtration system.
While we have seen many articles on water purifiers lately, none seem to offer any new information. While this is disappointing, it is also surprising that the supposed professionals authoring such reports are not well-grounded in this field.
Kindly check below for the summary of the full text. It will come in handy if you are short on time or not interested in reading the entire content. We recommend that you pay special attention to the conclusion.
[Recommended water purifier brands] – Which brand of household water purifier is better for each role?
– Suitable for short-term use in a rented apartment: Water Filter Pitcher.
– Suitable for a self-owned house: the intelligent, tankless water purifier with a modern design
– the Waterdrop, Frizzlife, Oasis Osmosis Home.
– Suitable for a self-owned house while keeping costs down: Express Water, APEC.
– High-end and sterilizable products: Waterdrop.
[Cost-effective water purifier recommendation] — How to choose a household water purifier?
– Under $200: Traditional RO filtration system, water filter pitcher, under sink water filter.
– $300: Waterdrop G2 reverse osmosis filtration, OASIS OSMOSIS HOME
– $350: Home Master TMAFC-ERP, Waterdrop G2 P600 reverse osmosis filtration.
– $400: Waterdrop D6 reverse osmosis filtration, GreatWell ROG400 reverse osmosis filtration
– $450: Frizzlife reverse osmosis filtration
– $550: Waterdrop G3 reverse osmosis filtration
1. Is a household water purifier necessary?
To make drinking water as safe as possible, the US Environmental Protection Agency (EPA) has established safety standards for groundwater and surface water under the Safe Drinking Water Act (SDWA). However, each state may set independent standards that may be stricter than the EPA’s. But despite these standards, there have been many scary drinking water safety crises in recent years.
Let’s start with this. On Nov. 10, the state of New Jersey filed a lawsuit against Solvay Specialty Polymers USA, alleging in part that the company has been using replacement PFAS at its manufacturing facility for over two decades, thereby polluting water supplies to New Jersey households.
In the same vein, on Sept. 28, 2020, the presence of a brain-eating amoeba in the drinking water of Lake Jackson, Texas, led to the issuance of a “Do Not Use Water Order,” followed by an emergency declaration by the state.
Recently, several environmental protection organizations also initiated a lawsuit against the EPA, accusing it of lax emissions standards for power plants, causing water pollution and health problems to residents around the area.
Asides from these known significant incidents, we still have on our hands more serious issues we should not ignore. The water supply system uses many chemicals in disinfecting drinking water, and most water pipelines used in delivery are old and decayed. Both situations can tamper with the purity of the drinking water and put households at health risks.
Under such circumstances, which is beyond anybody’s control, it is logical and necessary for everyone interested in clean, pure, and safe water to install a water purification device in their homes.
2. How to choose a household water purifier?
There are two main types of water purifiers: ultrafiltration water filter system and RO reverse osmosis water filtration system. Whichever you prefer, you can use the method below to choose the right model for your household.
The Three “How” Methods
You can choose the right water purifier for your household by answering these three important “How” questions.
(i) How much can you spare? Set a rough range.
Set the highest price point you can go for a water purifier before you proceed to shop online. Can you spare only $200 and below? Or you can spare more? You may not have a limit in some cases, provided the product is excellent – this is acceptable.
Each price point is a function of the capabilities of the product and how long it can serve. We recommend setting a range and picking a water purifier in your set range for the best results.
(ii) How large is the water purifier? Factor-in your countertop and under-sink space.
There are large and small water purifiers, countertop and under sink water purifier. The right choice will depend on how much kitchen space you can spare. That said, here are a few rules of thumb:
- Go for countertop water purifiers if there is no space in your cupboard.
- Go for a Tankless RO system, ultrafiltration water purifier, or under sink water filter if there is a small cabinet space or prefer a small-sized water purifier.
- Go for a traditional RO system if you have a sizeable under-cabinet space to spare, and you require no storage.
(iii) How is the filtration performance? Pure water or mineral water.
The major water purifier brands advertise how excellent their filtering is, basically saying 99.999% removal rate or a perfect 100% in some cases. However, each brand or model operates on a different filtering principle and packs various specifications.
For instance, some models offer mineral water as the filtered water while others offer non-mineral pure water. In such cases, your choice will depend on your preference.
If you apply these three “How” questions, you will most likely end up with 2-3 products that fit the bill, and choosing between them will be easier.
3. A Brief Introduction To The Characteristics Of Household Water Purifiers
The current market is filled with various brands of water purifiers, each with unique functions and product specifications. There may be differences in designs and appearances.
That said, we have identified four mainstream products above. Let’s take a look at each’s features, alongside the principle of water purifiers and how they work.
The different types of filter materials.
PP cotton: Removes large particles, such as sand, rust, etc.
High precision PP cotton: Removes small particles.
Compressed carbon block: Adsorbs chlorine, organic matters, bad odor, impurities, and heavy metals.
Granular Activated Carbon (GAC): Improves the taste and removes the unpleasant odor.
Ultrafiltration membrane: A kind of microporous filtration membrane with pore sizes below 0.01 micron.
Reverse osmosis membrane: Strong pressure forces water molecules to pass through the RO membrane. Except for hydrogen and oxygen molecules, other fine impurities can’t get through.
The working principle of a water filtration system is filtration.
A filtration system is equipped with different kinds of filter meshes, which keep impurities and odor out of the water, allowing only the clean and pure water to pass through. All water filtration products, irrespective of brands, employ the filter materials listed above – the PP cotton, activated carbon, reverse osmosis membrane, and others.
However, there may be slight differences in the filtration steps. Some products have their filtration process designed such that each step precedes another, for instance, from PP cotton to activated carbon block and RO membrane.
In other products, there is no particular order. For instance, the PP cotton and activated carbon block may be used repeatedly to ensure clean water. In comparison, the RO membrane is usually adopted once due to the high pricing.
This RO membrane comprises many layers.
Some products integrate different materials into one filter. A composite filter can perform multiple filtration effects and save kitchen space due to its small size.
Although you can find a 4-stage filtration system and a 2-stage filtration system in the market, you may not find marked differences in their performance levels. The 2-stage filtration system may contain a 3-in-1 or 4-in-1 filter. In other words, a 2-stage filter with 5 or 6 layers of filtration is more potent than a 4-stage filtration system with 2 layers.
RO membrane is a popular material used in filters. It is important to note here that an RO membrane’s hole size is only 0.0001um, which is 1/1,000,000 of the human hair’s diameter. The size of bacteria and virus is over 5000 times larger than the hole size, and only water molecules can pass through it. This means that it prevents the passage of harmful substances and impurities. This is why the RO membrane is called an “artificial kidney.”
Water molecules will not be intercepted because of their small hole size. However, their passage is subject to applying a lot of pressure, which is required to push them through the RO membrane.
The higher the applied pressure, the faster the water molecules’ movement through the membrane, and the more filtered water is produced.
[Filtration system specification]
Water flow capacity: A 400 GPD means the system can only produce 400 gallons of clean water per day. The higher the GPD, the more the amount of clean water produced. The highest water flow capacity in the market is 600 GPD, offered by Waterdrop, Frizzlife, and Oasis Osmosis Home filtration systems.
Water flow rate: This is the speed at which water flows through the faucet outlet. It is measured in L/Min (liters per minute), i.e., the number of liters of water flowing out of the faucet in a minute. The flow rate is proportional to the pressure applied. Higher pressure means a faster water flow and a lesser waiting time to fill a cup of water.
Drain ratio: Sometimes, you find water passing through the membrane effortlessly. Other times, you see water not passing through the membrane even with applied pressure. The latter is due to bacteria and impurities in the water flowing into sewage pipes—the less sewage produced, the higher the water production capacity. Most filtration systems offer a drain ratio of 1:1 or 1.5:1. The best drain ratio is 2:1, i.e., two cups of filtered water and a cup of wastewater for every three cups of feed water filtered.
Storage tank: The filtration system with a tank can filter water without much pressure. It can dispense water at a low speed and store clean water in the tank. The advantage of this kind of design is the low price. However, a notable disadvantage is the possibility of the stored water in the tank breeding bacteria and secondary contamination—most filtration systems with a storage tank a GPD of 50. Conversely, a tankless filtration system requires more pressure and a higher-quality RO membrane to dispense filtered water on demand.
Filtration stage: As mentioned earlier, the number of filters is not an indication of how good a filtration system is. Instead, the number of filtration stages is a better indicator.
Rated water capacity: Do not fall for advertisement gimmick where manufacturers claim that their filters can be used for 2 or 3 years. This projection is incorrect because they don’t know your daily water consumption. If the machine dispenses large amounts of filtered water daily, it may not last beyond a couple of months. Conversely, if you only require filtered water once a month, your filter may last for a decade.
Lifespan: This means that a filter’s life span is best estimated based on the rated water capacity and not the number of years. If a filter’s rated water capacity is 3300 gallons, it means that the filter can only dispense 3300 gallons of clean water. Once this capacity has been reached, the filter is due for a replacement, irrespective of the number of years it has served for. The larger the filtered water capacity, the better.