RO vs UV : Is RO better than UV

While certainly there is no shortage of options to choose from when you filter your water besides Reverse Osmosis (RO) or Ultra Violet (UV) water systems, both of these water systems are two significant systems that can give you clean and pristine water. They filter or kill the contaminants and unsafe microbes in the water. Before deciding on which system to settle with there is a whole package of different factors to consider.

Here are the key contrasts between the two water systems.​

RO vs UV Water Systems 

UV Water Purifier Pros and Cons 

The UV water purifier is effective in killing all the microbes present in the water. It comes equipped with a light source, preferably a tube, which is folded in a transparent protective sleeve.

The tube is kept mounted in such a manner that as water passes through the chamber it gets exposed to the light rays and it gets automatically absorbed into the water stream. 

The high-level wavelength UV light penetrates to the DNA level of microorganisms. The nucleic acid of the organisms absorbs the UV energy, scrambling the DNA structure thus rendering the cell sterile. 

This is very effective in preventing their reproduction; containing their numbers and effectively reducing their population down to a more tolerable level that is safe for consumption. The UV ray is very effective in killing bacteria, protozoa, and viruses.

These energy-rich electromagnetic rays are in the range of the invisible short wave light having a wavelength from 100 to 400nm. It has to achieve a much higher wavelength to make it effective in the elimination of microbes. In this case, the required wavelength should be at least 350nm to make it effective and make the water potable and safe for drinking. 

These Purifiers have what water filters have and what is more amazing purifiers are that it retains the mineral and traces of elements in the water which is good for your health. It also maintains the pH balance of the water and ensures the appropriate water chemistry.

The system is quite affordable, it purifies the water quicker than a reverse osmosis system and it’s easy to maintain. This does not require huge assembling and maintenance charges as you can replace the bulb inside the system. The reverse osmosis systems depend on power to support the water pressure but the UV channels can work with ordinary water pressure. 

Additionally UV water purifier saves money on some other significant aspects like time and keeps the water in its characteristic shading and taste.

A major drawback regarding the UV water purifier is that the UV does not filter the dead microorganisms. They remain suspended in the water. 

It’s also quite possible that the water is generally contaminated with everything from pesticides to prescription drugs. The UV water purifier will do nothing to remove these contaminants. 

The UV water purifier is not equipped to remove broken-down solids from the water.

Moreover, the turbidity of the water can also alter the effectiveness of this system. The incoming water passes through the quartz tube surrounded by the UV light, but when the tube becomes covered with a dirt film the light cannot penetrate through. Hence you need to keep watch of the turbidity to make the system more effective.

Due to that, it’s recommended you buy a UV water purifier that comes with adequate pre-treatment facilities like a pre-filter and an active carbon chamber. Such a system is very effective in removing both physical and organic contaminants.

Before you buy a UV water purifier, opt for a reputed brand because a renowned brand never compromises on quality and advanced technology. Some systems come with a monitoring system.

The system will automatically monitor the quality of the output water continuously. In case the purification level drops below the pre-determined standard, the system shuts off robotically. The advantage of using the system is that ultimately what you get is water that is physically, organically, and microbiologically 100% pure and safe.

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Reverse Osmosis System Pros and Cons

A reverse osmosis system is a type of membrane filtration that removes 90-99% of the impurities in water, making it one of the most effective and economic options for water purification. 

One unique characteristic of a reverse osmosis system is that it removes all dissolved salts, metals, and chemicals from the water. The system is very effective in removing 99% of non-living contaminants as well as microscopic organisms such as bacteria and viruses. 

How does it work? The Reverse Osmosis system works by forcing water through a membrane. The membrane has vastly smaller holes-pores that are thousands of times smaller than what is in a typical filter.  

It uses pressure to force a solution through a membrane retaining the solute on one side and allowing the pure solvent to pass to the other side. However, the effectiveness of the system depends on the water pressure as well as the initial stages of the pollution.

There are 3 basic types of reverse osmosis filters depending on the type of membrane used. Cellulosic, Thin-film composite, and Aromatic Polyamide.

The cellulosic membrane is easily fouled with bacteria but can withstand chlorine. Thin-film composite membranes should only filter water that has passed through chlorine first. Aromatic polyamide membrane is resistant to bacteria but is easily broken down by chlorine.

In Reverse Osmosis, Contaminants and solids don’t pass through the membrane so the water coming on the other side is very pure. 

The Reverse Osmosis system has an underlying pre-filtration framework that removes the smallest disease-causing bacteria such as E.Coli, cholera, and Salmonella. It also removes chemicals, heavy metals such as arsenic, copper, and barium; broken down salts, sand, rust tiny particles, odors, cloudiness, and sediment. The system lowers your TDS (total dissolved solids) level to 0 which means you have no solids in your water. 

Some public water supplies have contaminants such as, cadmium, chromium, fluoride, cysts and which are some of the worst things that can be in the water. 

Not only that, the system removes the foul odor and taste of the water.

Subsequently, the cleaned water is more sterile. The Reverse Osmosis system demineralizes the water which means that it removes the trace minerals that are so important to our health. Drinking demineralized water regularly can lead to mineral deficiencies.

Besides that, the reverse osmosis system can be very expensive. The system also uses a lot of water as it needs massive water pressure to push through the membrane. For every 1 gallon of clean drinking water produced as much as 5 gallons is used as wastewater. Experts prove that this system can only recover up to a maximum of 20 percent of the water going into the system.

Another disadvantage of using a reverse osmosis system is the wastage of electricity. It requires additional power being supplied to the pumps to pressurize the water entering the system. This means that both your electricity bill and water bill will go up higher.

The units themselves are somewhat large and need to be installed underneath your kitchen sink.

Another disadvantage is that under the sink style of water filters will only filter the water delivered through that single faucet. You will need to use an additional filter on your shower to prevent chlorine into the air every time you shower.

Also, it might be too difficult for you to install one of these filters by yourself unless you are a DIY person.

Also, chlorine can damage the membrane, so consider a combination filter that removes chlorine first or choose a reverse osmosis filter that has a cellulosic membrane. 

Besides, the reverse osmosis system frequently needs higher maintenance. Make sure you perform regular maintenance on your filter even if it doesn’t appear to need it. The reverse osmosis membrane can become worn and form tiny holes that bacteria can pass through. This means that the system is more costly than other normal water filter systems.

Replace the membrane and cartridge as often as recommended by the manufacturer to keep your water filter in top working condition.

The Reverse osmosis system provides some of the most refreshing and purified drinking water available. They are one of the best ways to ensure that you’re not drinking tainted water.

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Whether we’re dealing with a mounting environmental crisis or are simply doing a better job of testing and understanding our drinking water, there’s no doubt that more people than ever before are worried about their water.

It is but a surprise that only less than 1% of the available water on earth is safe for consumption; the rest 69% is unsafe. With the increasing pollution levels and presence of microbiological contaminants in water, water-borne diseases have seen a rise too. Statistics point that almost 80% of the prevalent diseases are waterborne.

In light of this, it’s important that only use the right and advanced water purifications systems that one can stay safe from such diseases. The UV water purifier and Reverse osmosis system are examples of really effective water systems.  

Marcus Reynolds
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