Thursday, June 29, 2017

Reverse Osmosis (RO Water) 101

Reverse Osmosis (RO) systems are a popular water filtration systems for drinking and cooking water. Household RO systems are typically located under the kitchen sink and supply you with filtered water out of a separate smaller faucet on your sink. The RO system is made up of several pre and post water filters, usually a sediment/carbon combination, and a RO membrane which allows the system to do the process of reverse osmosis.  Even though these systems are very popular, a good amount of people still do not know much about them.  Below I will go over some of the most common questions about RO systems we hear.

How Does it Work?

RO systems work by filtering water through a variety of filters (usually carbon and sediment) to rid the water of most of its visible solids. Next the water goes through the RO's membrane which allows it to do the process of reverse osmosis. Reverse osmosis is the process in which water is forced under pressure through a semipermeable membrane. This process allows RO systems to not only filter out any remaining visible solids from your water but dissolved material too. Meaning the reverse osmosis removes more than 90% of all contaminants and impurities found in your water! The contaminated water is drained away and the filtered water is then fed into your RO tank. Some systems will also have a post filter to filter the water coming out of the tank one last time before it pours out of the faucet.

How Often do I Need to Change the Filters?

It's recommended by the manufactures to change your pre and post filters every 6-12 months, and the membrane every 2-5 years. However in warm weather climates where the tap water stays in the mid 80 degrees all summer long, it's recommended not to go over 6 months. This is because the warm water is ideal for bacteria growth. Regular filter changes will also help prevent leaks and extend the life of your RO membrane.

If I Don't Use my RO Much do I Still Need the Filters Changed?

Yes! Not using your RO is possibly the worst thing you can do to it.  It will allow the the water to grow stagnate around the filters and in the tank, resulting in bacteria growth. Not using your RO will also cause your system to be more susceptible to leaks and other issues. The best rule of thumb is to use your system as much as possible to keep water moving through it, as you will still need to change the filters if you don't.

Is There a Way Not to Waste as Much Water?

Yes there is! Most reverse osmosis systems have a 3:1 ratio on water use.  What this means is they use up 3 gallons of water in order to make one gallon of RO water.  Recently some manufactures have developed a new "Green" membrane (such as the Pentair GRO-50EN) which allows the reverse osmosis to use only 25-35% of the water used by a conventional RO system. To put it simply it drops the ratio from 3:1 to 1:1!

Are All RO's the Same?

Yes and no.  All RO systems do the process of reverse osmosis that we talked about above but not all RO systems are made the same.  In the world of RO's there are two main types, Proprietary ROs and "Standard" ROs. Proprietary systems are systems that are "unique" to a certain manufacture. What this means is that these systems are built so that their parts and filters can only be purchased through that manufacturer, sometimes at a much higher cost. "Standard" systems, as we call them, are systems that use universal filter sizes that you do not need to go through the manufacturer to get. There are also systems that use specialty filters and parts, such as the "Green" membrane we spoke of before. These filters and parts allow your system to do something most other systems can't.  Such as dropping the water usage, balancing the PH level, reintroducing healthy minerals into your water and more.

There you have it our most commonly asked questions about RO system answered. If you have a question about RO systems we did not answer here or if you would like to schedule an RO filter service please visit!

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