Help! I’ve fallen and I can’t RO

Are you lost, confused, afraid? Have you found yourself scouring the internet getting sucked into hours of DIY youtube videos? Are you looking at your reverse osmosis filtration system like it’s an untrained emergency tracheotomy on a turbulent plane? Fear not! This article is for you.
“I have an Omnipure filter system and I need to replace the filters but I don’t know what I’m looking for, or how to do it?” We must receive this call at least 6 times a day most days. The shocker is that Omnipure doesn’t actually produce any complete systems.

We make filters yes, but in most cases our filters are used as components in complete systems made up of different parts and brands. Before we dive too deep let’s look at an “average” 5 stage system and learn some of the parts. Keep in mind that RO systems come in many different shapes and sizes but the way they work is generally the same.

  1. Sediment pre filter housing.
  2. Carbon pre filter housing.
  3. Carbon pre filter housing.
  4. RO membrane.
  5. Carbon post filter.

The first stage, or (A) is all about removing any larger sediment particles from the water. Dirt, sand, or George Washington’s wooden teeth are no match for this simple fibrous filter. Wondering how that got in there? Anyone who’s been to the beach can tell you, sand can get into anywhere.

The second and third stages, or (B) and (C) pass the water through carbon filters. This removes many contaminants but most importantly it removes chlorine. This is vital because chlorine degrades many RO membranes leading to fouling or plugging. Omnipure carbon blocks work great in these stages (shameless product plug… check). Simply disconnect the housings, (stage B & C) pull out the old carbon element and insert the new Omnipure carbon block element.

Stage four, or (D) is the Reverse osmosis membrane. This is as they say, is where the magic happens. Filtered water is forced via your house water pressure through a semipermeable membrane. The pores of the membrane are so small that nearly everything besides the water molecule is too big to pass through. When it comes out the other side you have super clean RO water. All the left over stuff is rinsed off the membrane and pushed out of a drain line into your main drain. The clean water moves to the storage tank until you need it.

Stage five, or (E) is the carbon post filter. It usually sits atop everything else and is the last filtration step before the water goes to the faucet. This final step “polishes” the water to remove any taste, color, or odor it picked up in the tank. It is also the first label people notice, hence why we receive so many calls. Our K-series and CL-series are widely used as post polishing filters.

Holding all these parts together is the manifold. If your system has a brand name it would be here. Many systems are generic, allowing for personalization based on your water quality needs. For the most part regular replacement of the filters is all the maintenance you need, however other parts may wear out. Common parts that need replacement are the housing o-rings, and filter fittings (the parts the water line plugs into.) Now that we know what we are looking at we can go over a few do’s and don’ts of replacing your water filters.

  • Do… shut off your water to the system. Unless your kitchen can float make sure your water is off before you start taking stuff apart.
  • Don’t… skip that step. Seriously, water damage is no fun.
  • Do… take notes on how everything is hooked up. A couple pictures could help as well.
  • Don’t… wait too long to replace your filters. Replacing filters per manufacturer instruction keeps your system working well and water tasting great.
  • Do… invest in proper tools. A filter wrench can save a big donation to the curse jar.
  • Don’t… hesitate to call a water professional if things go wrong. They will have you fixed up in a jiff.  

Hopefully you know a little more than you used to, and looking at your RO system is a little less terrifying.  Need to get some filters? Take a look at our distributors here (link to distributors map) Stay safe, stay hydrated.

The other “C” word

We folks who live in cities with water distribution systems have got it pretty good. Safe drinking water that is available at our whim, a luxury that is easily taken for granted. Our drinking water is made safe largely because the big “C” word, chlorine. Chlorination is the process of adding chlorine to drinking water to disinfect it and kill germs. It helps kill “bugs” like cryptosporidium. No, that is not an alien planet from Star Trek, it is an illness causing parasitic protozoan cyst. Unless you are a fan of gastrointestinal chaos, you’ll be glad it’s out of your water.  

Chlorine does have some downfalls; it naturally dissipates from water over time. Sometimes there is not enough chlorine left to keep water disinfected before it reaches the end of the distribution system. Another issue with chlorine is that as it disinfects water it releases by products, or disinfection by-products. The EPA has stepped up regulations on DBP’s leading to municipalities looking for alternatives to chlorine. Enter chloramine. I know what you are thinking, chloramine, more like boramine.  It may not be the most exciting topic, but if you care about what is in your water then you may want to read further.

So what is it you ask? Chloramines are a group of compounds made up of chlorine and ammonia. The particular type used to treat drinking water is called monochloramine. It works in much in the same way as chlorine, disinfecting water making it safe to drink. In a compound form it is far more stable than free chlorine. This helps chloramine continue to disinfect water throughout the distribution system clear to the point of use, i.e. your home. Chloramine has been used in parts of the US since 1929. An EPA survey estimated that in 1998 68 million Americans were using water disinfected with chloramines. That number has grown and is continuing to grow.

One positive attribute of chlorine is that once it does its job, it is very easily removed from water at the point of use. A simple carbon filter and voi la, you have great tasting chlorine free water. If you use an RO system then it is especially important to remove chlorine and chloramines before they reach the membrane. Chloramines being very stable, are far more resilient than chlorine, and require some extra effort to remove. The most effective treatment is catalytic carbon. The reason for its effectiveness is in its name. Catalytic carbon acts as a catalyst causing chemical reactions that break the bond between chlorine and ammonia letting the carbon absorb the chlorine and break down the ammonia. Are you flashing back to 10th grade chemistry? Don’t worry, this isn’t on the test. What you get after is safe treated chlorine/chloramine free water.

As chloramine treatment rises, so does the technology to take it out of water at the point of use. There have been some promising breakthroughs in the development of catalytic carbon leading to far more effective results and longer carbon life. That means less filter replacements and more great tasting water.

Unsure how your water is treated? Look up your local CCR or consumer confidence report. Each community water supplier is required to provide a CCR once a year. It details testing, contaminants, and treatments. If you are looking for point of use treatments you can find more information at Stay safe and stay hydrated.   



Chloramines in Drinking Water, EPA, Accessed 4 Oct. 2018.

Disinfection with Chloramine, CDC, Accessed 4 Oct. 2018.