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Sweetwater's Custom

Reverse Osmosis System


 Sweetwater's custom reverse osmosis system


Sweetwater's Custom Reverse Osmosis System is designed to provide high purity water


There are situations where the appropriate drinking water treatment consists of reverse osmosis. This is generally due to the presence of pharmaceuticals, radioactive metals, nitrates, arsenic, fluoride, or high levels of total dissolves solids (minerals, aka tds). These contaminants can only be removed by the use of a reverse osmosis system.

I start with a 5 stage NSF certified reverse osmosis system manufactured by Watts Water. I modify this by adding a KDF/catalytic carbon filter to oxidize arsenic 3 and remove chloramine and a calcite filter after the system to raise pH and improve taste. The tds of the reverse osmosis water will be about 30, similar to mountain water in Seattle, San Francisco, Portland, Denver, or NYC.

Reverse Osmosis is poorly understood by most consumers and some individuals feel the need to say negative things about the technology. Two issues stand out:

Doesn't a reverse osmosis system 'waste' water?

This is a very human centric view. We only find water to be used efficiently when we pee in it. Reverse Osmosis systems do use more water than simple water filters and have a waste stream. The waste stream cleans the membrane while purified water is being produced. The 'waste water' is carrying the contaminants which you do not want to drink down the drain. The following illustration shows the technology:


Some people object to the use of reverse osmosis systems due to the alleged water 'waste'. My view is that the water is used to provide you with highly purified water for drinking and so it is not wasted anymore than any other water you may use. Your choice is often to either purify the water or drink extremely harmful contaminants. You can read more here. There are tools, such as pumps you can use to reduce the waste water stream but I generally recommend against buying them - because plumbers often install them incorrectly and they add to the complexity of a system that is otherwise pretty simple and easily maintained by a homeowner/consumer.


The second objection relates to the first one. That is, that reverse osmosis water contains no minerals and drinking it will strip minerals from your body. This is nonsense. The body does not work this way. Reverse osmosis systems do remove minerals from water, along with dangerous contaminants. This will result is a sharp, crisp tasting water with low pH. I counter this objection with the addition of a calcite filter that raises the pH, adds alkalinity and a bit of calcium. Minerals in water do not matter. Just think for a minute about the citeis I mentioned above; Seattle, San Francisco, New York, Portland, and Denver all have extremely low levels of minerals and there are no health concerns in those cities that are related to their water.


Still others claim that reverse osmosis water is 'dead'. This is more nonsense. There is no such thing as dead water. Please read my comments on this topic here.


In fact, Sweetwater's customized product provides water with a high level of purity. It eliminates contaminants from your water that ordinary water filters do not. In many situations reverse osmosis water is your only option: either that or continue to drink contaminants in your water that may lead to cancer or other cellular disorders. Please take a moment to read this article about the dangers of drinking water containing pharmaceuticals. Be sure to look at the European studies which show these to affect cell function. Pharmaceuticals in drinking water are not regulated in the United States yet. And they are present in your water anytime your water source is a river with cities upstream.

Sweetwater's custom reverse osmosis system consists of a total of six stages, though I often refer to it as five stages plus calcite filter. This is because almost everyone asks about pH or remineralizing filters so by mentioning it separately I hope to point out that it is included. The stages are as follows:

5 micron sediment filter - removes dirt from pipes

KDF/catalytic carbon - creates an antibacterial environment, oxidizes arsenic 3, and removes chloramine

Coconut carbon block - removes the remaining chlorine and chlorine byproducts

reverse osmosis membrane - this is the actual reverse osmosis process. It removes numerous impurities including metals, nitrates, pharmaceuticals, etc.

The water then goes in to a storage tank which holds up to 3.2 gallons. After leaving the storage tank:

Inline carbon filter - to remove impurities and improve taste

Calcite filter - to raise pH and improve taste

Read my comments on my competitors 'remineralizing filters'.

Sweetwater's custom reverse osmosis system sells for $675 plus shipping.

You may request the specifications for the reverse osmosis system I sell here:

 Send me your reverse osmosis specifications and pricing


Here are two examples of mounting options for Sweetwater's custom reverse osmosis system. The first photo shows a typical under sink installation:



This next photos shows an installation in the basement just below the kitchen sink:


If you're wondering whether you need a reverse osmosis system or a simple water filter stat by looking at your local water report. The contaminants i've mentioned above can only be removed using a reverse osmosis system.


Request my reverse osmosis system specifications and pricing here



My name is James P McMahon and I bring healthy water to people one family at a time


ecologist James P McMahon




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