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Frequently Asked Questions about Reverse Omosis

Reverse Osmosis Systems

What exactly is “Reverse Osmosis”?

How does Reverse Osmosis work

To understand the principle of “Reverse Osmosis”, let’s first have a look at what “Osmosis” really means.

Osmosis is a natural process wherein solvent (water) molecules spontaneously migrate through a semi-permeable membrane from a region with lower solute concentration to one with higher solute concentration.

Osmosis is a very important phenomenon in nature - osmosis is responsible for the ability of plant roots to draw water from the soil; osmosis is responsible for the flow of liquids and of dissolved solids and gases into and out of living cells. The movement of the solvent across the semi-permeable membrane is driven to reduce the free energy of the system by equalizing solute concentrations on each side of a membrane, generating osmotic pressure. Applying an external pressure that is greater than the osmotic pressure can help in further movement of the solvent, beyond equilibrium.

For purification of water, as you can imagine, the concentration of salts and minerals (in other words, solutes) is higher in the feed water (solvent). So, when the water is passed through a semi-permeable membrane, we want the water to move in the direction of high solute concentration to low solute concentration (opposite to the natural flow during osmosis). Hence, this process is called “Reverse Osmosis”. This is the principle of operation of Reverse Osmosis Water Systems

How does a Reverse Osmosis System work?

Reverse osmosis water systems work by passing pressurized water through a semi-permeable membrane, so that the permeate water (purified water) is stripped off of almost all the dissolved salts and other impurities, thereby purifying it. The membrane is designed to allow only water to pass through this dense layer, while preventing the passage of solutes (such as salt ions). This process requires that a high pressure be exerted on the high concentration side of the membrane, usually 2–17 bar (30–250 psi) for fresh and brackish water, and 40–82 bar (600–1200 psi) for seawater, which has around 27 bar (390 psi) natural osmotic pressure that must be overcome. 

Reverse Osmosis Membrane

Why Reverse Osmosis instead of bottled water?

The debate of bottle water vs. Reverse Osmosis water is short. Reverse Osmosis water tastes better!! Bottled water plants use filters to remove contaminants from the tap water. Filters work but only to a certain extent. Many contaminants are left in the water. Another downside of bottled water is that the water is held in plastic for months before consuming. This leaves the water susceptible to toxins left by the plastic in bottles. Also plastic is bad for the environment. Even if you were to recycle, it takes energy to reuse the plastic for use again. Bottled water is also far more expensive over time than a Reverse Osmosis System. In the end there is no debate: RO water beats water in plastic bottles in every category.

Can I drink my city's tap water?

It might not be a good idea. Sure every now and then it won’t do any harm but the water your city puts into the waterlines is not constantly checked for contaminants. The contamination in the water can happen anytime in the delivery to your home. The chemicals that our neighbors dump out into the streets and toilets end up in the water supply. Millions of tons of medical supply are dumped into the environment every year, eventually ending up in the water supply. Major corporations also dump tons of waste into the environment. Think Erin Brockovich? The famous movie bringing to light the carelessness of major corporations. If you know you live in an area known for lower quality water, we strongly recommend not drinking the tap water.  

How effective are RO systems compared to other methods?

In short, RO systems are the most convenient and effective method in water quality. The water is pushed by so much pressure through the membranes there is almost no chance for contaminants to get through. The result is pure water. It is so powerful that it is the only water system that can take salt water and filter out the saline, leaving quality drinking water.  

The rejection rate of contaminates is also one of the highest for water filter systems. The more common contaminants have a rejection rate up to 99.9%, unheard of for other water filters.

Is installing a RO system hard?

Installing a Reverse Osmosis System is not too challenging for the typical home owner. Any handy homeowner with basic skills can get the job done fairly easily. On a scale from 1-10, 10 being the hardest, it would be a 3. So most people can get the job done without a sweat. If you are really lost with this type of work, then ask a plumber to install your system. About 95% of home owners can do it themselves.

Don’t we need some minerals In the drinking water?

This is one of the biggest myths in RO systems. Indeed we need calcium, magnesium, and sodium but we do not need it from water. We can get these healthy minerals in the foods we eat. Because a filter cannot tell the bad minerals from the good ones, we cannot filter specific minerals. The reality is if we could get spring water from the mountains that have not touched any human toxins, then it would be great, but the reality is our water is mixed with too many human elements and bad toxic chemicals for this to work. So while you can use some healthy minerals an RO system takes out, it’s not worth the risk.  Here are some "bad" minerals an RO system DOES takes out:

Certified Contaminants Reduction %
Chromium (Hexavalent)
Chromium (Trivalent)
Radium 226/228

Where do you install the RO system?

Most systems will be placed under your kitchen sink, connecting from a line up to your faucet. The systems are fairly small and compact, so you can expect these systems to keep clear in your sinks storage space. We also sell whole house systems that can be connected to the main water line usually in your garage. These systems provide RO to all taps of the house.

Do all RO systems come ready to install?

Yes, all systems come shipped ready for easy installation. You may require some tools to get the job done, but all systems are shipped with a tank and faucet ready for use.


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