How to choose a reverse osmosis filter: ranking of the best manufacturers and their products
Almost every one of us thought about the quality of the consumed water. Buying bottled water daily is very expensive in practice, and tap water without further purification is completely unsuitable for this purpose. Do you agree?
It turns out that this problem is quite easy to handle. Using a reverse osmosis filter from a trusted manufacturer, you can be sure of the quality of the water used. In the huge assortment of reverse osmosis systems on the market, making the right choice is not easy, but we will help you find the right solution.
In this article, we will talk about the principles of operation of reverse osmosis filters, the criteria for their selection, provide an overview of models from the best manufacturers, and also give recommendations on the operation of filters. The material is accompanied by thematic photos and videos.
The content of the article:
- Forward and reverse osmosis
- The principle of operation of such a filter
- Filter system selection criteria
- Rating of the best systems for water purification
- Filter Recommendations
- Conclusions and useful video on the topic
Forward and reverse osmosis
Natural osmosis is a phenomenon that underlies the metabolic process that occurs in living organisms. It provides a balanced state of salt and mineral metabolism.
Living cells are washed by blood and lymph, from these liquids through the membrane, which is a semi-permeable membrane, nutrients enter it, and waste products are removed back.
The semi-permeable membrane has selective throughput. Having an electric charge on its outer surface, it repels mineral substances dissolved in water, whose molecules, as a result of hydrolysis, decompose into ions.
In the middle of the cell, these mineral substances carry special transport molecules through separate channels available in the cell membrane.
To simulate the process in the laboratory, take a vessel, divide it into 2 parts using a semipermeable membrane. A highly concentrated aqueous solution of a mineral substance is poured on the right side of the septum, and on the other, the same, but in a much lower concentration.
Striving for equilibrium, the water on the left side goes to the right. The process continues until the concentration of solutions on both sides becomes the same.
With the achievement of an equal level of concentration, the height of the liquid columns located on different sides will turn out to be uneven. The difference in height will be directly proportional to the force that causes water to pass through the membrane and is called osmotic pressure.
Reverse osmosis - a phenomenon directly opposite to natural osmosis. Everything in the same vessel, under the influence of external pressure on a solution of high concentration, water changes direction. The applied pressure simply pushes it through the membrane, freeing from the substances dissolved in it.
The concentration of the solution, which was already higher initially, rises further, while the smaller one continues to decrease. Through the membrane, as before, only water passes, but in a different direction.
Recommended related article: Reverse osmosis: the harm and benefits of membrane purification of tap water.
The principle of operation of such a filter
The principle of water purification using reverse osmosis based on the fact that a concentrated aqueous solution is supplied under pressure into a container separated by a semipermeable membrane. Water filtered through the membrane gets into the second part of the tank, mineral substances remain outside it, and then go to the sewer.
Filters consist of modules that are easily replaceable during operation. Each of them has a specific service life.
The system design includes several filter cartridges with activated carbon and porous polypropylene inside. With their help, water is freed from solid particles and organic impurities. At the first stage, when passing through a polypropylene filter, water is freed from particles with a minimum size of 0.5 microns.
The second filter is a carbon filter, with its help organic and chemical impurities are released from water, including oil products, pesticides, heavy metals and other substances. The last filter in front of the reverse osmosis membrane retains microscopic mechanical impurities; their size does not exceed 1 micron.
The main element in the system is the membrane, where water flows under pressure after rough pretreatment. Its pores with a size of 0.0001 microns do not pass anything but water molecules. When it passes through the post-filter, the final purification and stabilization of water occurs.
Here, the stream is divided into two parts: crystal-clear water and a concentrated solution discharged into the sewer system. Pure, boiling-free water enters the storage tank, and then through a separate tap to the consumer.
The system is designed so that as the flow of purified water, its reserves are replenished automatically. From the inside, the tank consists of 2 chambers with a silicone membrane as a partition between them. Water enters the upper compartment, and compressed air is located in the lower compartment.
When the volume of water decreases, the membrane expands, maintaining pressure until the water is completely drained. The air pressure can be adjusted by means of a nipple mounted on the side of the lower chamber.
For individual selection of drinking water, a special faucet is cut into the countertop or kitchen sink, which does not depend on the flow that is used for other purposes.
Some manufacturers provide their products with additional functionality:
- mineralizerintroducing useful trace elements into the water that the membrane did not miss;
- ultraviolet lampkilling harmful microbes;
- structuralistrelieving water from "negative" information.
Water consumption during such cleaning cannot be called economical - upon receipt of 1 liter of potable water, 3 liters of dirty water go into the sewer. For the system to work, pressure is required within 2-6 bar, so sometimes it needs to be increased with a pump or lowered using a gearbox.
Filter system selection criteria
Cost reverse osmosis filters pretty high. Their choice must be approached responsibly, having previously assessed their capabilities financially, both for the moment and for the future, given the need for periodic replacement of modules.
It should also be understood that most filters purify water very slowly. The speed of passage of water depends from pressure in the water supply, concentrations of various impurities in water, membrane permeability. Count on their great performance is not worth it.
So how do you choose a reverse osmosis filter?
The best choice will help to make an assessment according to the following criteria:
- The number of cleaning steps.They can be from 3 to 9.
- The presence of additional functionality.
- The authority of the manufacturer.
- Material and number of stages of prefilters. Plastic should not be odorless. Checking its presence is easy, you just have to unwind the flask.
- Reliability of seals on flasks and connecting elements. The first should be double, and products from JohnGuest and Organic are considered the best compounds.
- The material from which the storage tank and the mounting plate are made.
- Membrane performance.
- The presence of a pump.
- Displacement of the tank.
- Resource membranes and cartridges.
- Type of flask. Cartridges of the “block module” type are more expensive than the “bulb-filler”, but their replacement is easier to carry out. A flask installed in a glass in an internal way is considered to be of higher quality.
- Correspondence of the dimensions of the structure to the availability of free space under the sink.
Of considerable importance is the design of the crane. There may be 1 valve for purified water or 2 if a mineralizer is included in the system.
The quality indicator is the color of the bulb. Its surface should be white or matte without streaks and impurities. A fully transparent bulb has very thin walls, and under the influence of high pressure they can simply break.
Often unscrupulous manufacturers use such a trick as increasing the weight of the flask, masking this flaw in the material. It produces an unpleasant odor. A good bulb should be neither very heavy nor too light.
Cases made from quality raw materials can withstand high pressure. They have smooth inner walls without the slightest hint of pores. Bacteria and particulate matter cannot penetrate such a surface. When using secondary raw materials, then microcracks are observed on the surface of the body, sometimes leading to splits.
Manufacturers use plastic or metal to make the tank. The latter is characterized by a longer service life, and the first does not rust.
When choosing, you need to proceed from the operating conditions of the cleaning system. For an apartment or a house where they live permanently, a model made of plastic is suitable, but for giving it is better to choose a tank made of metal. The volume of tanks of different models ranges from 4-12 liters.
Membranes for reverse osmosis filters are produced by many manufacturers.The cheapest are Chinese products. They are distinguished by a small resource and lower than average quality.
The most popular are Filmtec, Osmonics, Pentair membranes, manufactured under license from the United States and TFC from a manufacturer from South Korea. Under normal pressure in the system, they serve 2.5-5 years.
So, the following basic characteristics are especially important when choosing: the number of steps, the presence of additional cartridges and their service life, the presence of a pump, design dimensions, and performance.
Rating of the best systems for water purification
The range of household reverse osmosis filters is represented by a huge number of offers from different brands. Not all of them are worthy of attention. When choosing a filter for washing, you should pay attention to the manufacturer, user reviews, the duration of his stay in the domestic market.
In order not to doubt the quality of the purchased system, you can compare your choice with the rating of popular filters from professionals involved in the installation and maintenance of reverse osmosis water systems for a long period. The most popular brands include: Atoll, Leader Standart, Aquaphor, New Water, Barrier, Geyser.
Place # 1. Water filter from Atoll
This is a compact model with a 5-speed cleaning system. It is possible to install the tank in a separate cabinet with a lack of free space under the sink.
When replacing cartridges, you do not need to turn off the tap, tank and the system itself from the sewer. The membrane productivity of the household model is sufficient for the needs of a family of 3-4 people.
A membrane of high quality polymer material is produced in the USA. The design of the system is simple and affordable cost of maintenance.
The filter is insured against leakage by the excellent build quality and the fact that it uses John Guest fittings, the reliability of which has long been recognized in the world. The manufacturer comes with a designer crane for each model.
For the effective operation of the Atoll reverse osmosis system, the pressure in the water supply should be maintained at a level of 3 to 8 atm. If the upper limit is exceeded, a failure in operation may follow, a pressure reducing valve is necessary to prevent such cases. Pressure below 3 atm also leads to malfunctions if a structure without a pump is installed.
Place # 2. Leader Standart Filters
Leader Standart drinking systems are of high quality. They are produced in Poland and Korea.
Some filter models include a bioceramic cartridge, inside of which are sealed clay balls with the addition of tourmaline minerals. Their value is that they are long infrared waves that change the structure of water and give it healing properties.
Water passing through these reverse osmosis filters is purified at 97-99%. The manufacturer gives a guarantee for perfect work for 36 months.
Place # 3. Compact filter Aquaphor Morion
A relatively inexpensive and ergonomic filter, operating on the principle of reverse osmosis, was created by Aquaphor.
The device is equipped with a storage tank with a capacity of 5 l, built into the body, 3 replaceable modules, a module with a membrane, a set of tubes for connection, taps - inlet and for purified water, a sleeve for connecting the system to the sewer.
The first of the modules with a polypropylene filter performs mechanical pretreatment. Replace it with a frequency of 3 months. Deep purification is performed by the second module containing sorbents in the form of fibers and granules. With its help, heavy metals, organics, active chlorine are removed from the water. The frequency of replacement is every six months.
The membrane module is designed for ultra-deep cleaning. Passing through it, water is freed from bacteria, viruses, harmful impurities, nitrites, nitrates, salts, which give it rigidity.
Change this module every one and a half to two years. Final purification and mineralization of water takes place on the fourth module, which is subject to annual replacement.
Place # 4. Installation "New Water"
In addition to the reverse osmosis filter, the system is equipped with a mineralizer and bioceramic activator. New filter modifications from the New Water company are called smart systems. They are characterized by increased productivity, an unusual crane design, which has an LED indicator that responds to a hand brought to the body.
One of the new developments of the company is a full automatic, high-tech 6-speed system. It works on electronic control, equipped with a display, electric pump, electronic pressure sensors and valves. If the membrane becomes dirty, the electronic controller sets a special mode and flushes it.
The design of the filter includes a post-filter mineralizer with a silicon-schungite filler, enriching water with ions of potassium, calcium, magnesium, sodium, which increases its biological value. A storage metal tank holds 12 liters of water. Membrane productivity - 185 liters in 24 hours.
Place # 5. Reverse osmosis system "Osmo 100 Barrier"
The performance of this system is 228 liters per day. At a working pressure of 3 to 7 atm, the water goes through 5 stages of purification:
- “PROFILE BARRIER Mechanics 5 microns” holds solid particles larger than 5 microns. Inside the filter is food grade sprayed polypropylene.
- "BARRIER PROFI Sorption" purifies organics, chlorine, organochlorine compounds. Filler - activated coconut charcoal in granules.
- “PROFILE BARRIER Mechanics 1 μm” is the last preliminary stage of cleaning in front of the membrane when fine suspensions are screened out.
- "BARRIER PROFI Osmo" - the main stage of cleaning. The membrane is made of ultra-thin composite polyamide.
- "PROFILE BARRIER Postfilter", where coal enriched with silver is placed. Additionally cleans and enriches the water after the storage tank.
Membrane replacement is performed once every 1.5 years, and mechanical cleaning modules - once a year. The capacity of the plastic tank of the Osmo 100 Barrier filter is 8 liters.
A Russian company produces a filter, so its cost is lower than its foreign counterparts. Consumers do not complain about quality. The body of filters from the Barrier company is very strong. All filter elements are of decent quality.
Place # 6. The filter under a sink "Geyser Prestige"
Three stages of cleaning allow you to retain heavy metals, chloride salts, bacteria, viruses. The performance of cartridges is 0.13 liters per minute. A feature of the development of the Geyser company is a sorption device, which can only be purchased directly from the manufacturer.
The membrane throughput is 0.0001 microns, it allows you to purify water at the ion level. Change it 1 time in 1.5 years. The pressure required for the operation of the system is at least 3 atm.Under the name "Geyser Prestige" hides how many models, they are distinguished by additional characters.
The letter M in the name indicates that there is a mineralizer in the base set, P indicates the presence of a pump, PM - there is a pump and a mineralizer in the set.
The number 2 is present in the designation of compact systems with reverse osmosis. If the marking has the number 3, then the system has increased performance.
In addition to the quality of the system itself, the service life and the timeliness of the replacement of individual elements also affect the service life. The main condition for a long and uninterrupted operation of the system is optimal pressure. If it is within 4-6 atm, then the membrane works clearly, and the ratio between clean and dirty water is 1: 2 or 1: 3.
With a decrease in pressure, the force for forcing water through the membrane is not enough and a larger volume of water goes into the sewer, and the life of the membrane itself decreases.
There are other side effects: pre-treatment cartridges are quickly contaminated, the storage tank does not fill up completely, irrational water consumption increases, the filters of the housings are intensely silted.
You can recognize malfunctions in the reverse osmosis system by the following signs:
- Continuous murmur of water, indicating that water is discharged into the drainage continuously.
- An increase in the meter reading by 2-3 m3 per month from the usual.
- Contamination of primary cartridges for 2-3 months.
- A one-time drain from the storage tank in a volume of less than 7 l or a complete lack of water in it.
- No water flow through the open tap when the tank is full.
- The appearance of scale in the kettle and the water tastes salty.
- Extraneous sounds in the form of clatter when the pump is running, indicating frequent turning the pump on and off.
- The pump does not turn on.
- When the tank is full, the pump does not turn off and it is very hot.
- A hot power supply while the pump does not turn on.
- The water supply is turned off and the pump is running.
Incorrectly working filters form a negative opinion among consumers good filter systems. And sometimes you can correct the situation by simply installing a boost pump if the pressure is below 3 atm.
Conclusions and useful video on the topic
In order to fully understand the specifics of reverse osmosis filters and study the rating of manufacturers of water purification devices, we offer a selection of rollers.
Video # 1. Familiarity with the principle of operation of a dual osmosis filter:
Video # 2. Recommendations for choosing a filter for the preparation of drinking water:
Video # 3. Instruction for those who wish to independently install reverse osmosis filters:
Of all reverse osmosis systems, one cannot clearly single out one and say that it is the best. Their parameters are determined by the throughput of the membrane, the volume of the tank. It is believed that for good water quality quite 3 stages of treatment are sufficient. And the choice depends on the individual needs of each.
You want to share only the well-known subtleties of filter selection for you reverse osmosis systems? Have recommendations on using a drinking water treatment system or have questions? Please write comments.