Comparison Of Berkey® Purification To Reverse Osmosis

Comparison of Berkey® Purification Filter System to Reverse Osmosis and Distillation


Healthfulness of Reverse Osmosis and Distillation 


Based on current research, most health experts are no longer recommending drinking Reverse Osmosis or Distilled water on a long-term basis because these methods strip out all of the beneficial minerals from the water, making the water an acidic “hypotonic” solution. A chemist will tell you that when a hypotonic (de-mineralized) solution comes into contact with a “hypertonic” (mineralized) solution, the minerals within the hypertonic solution will transfer out of hypertonic solution and into the hypotonic solution until equilibrium is achieved. What this simply means is that when one drinks hypotonic water, the minerals in the blood and lymphatic system, which are hypertonic, transfer into the hypotonic Reverse Osmosis or Distilled water that is consumed and the minerals are flushed out of the body upon urination. In an effort to re-mineralize, the blood and lymphatic systems then begin to scavenge for minerals from other parts of the body, such as bones and other organs, and this process repeats itself every time de-mineralized hypotonic water is re-consumed. Several studies suggest that people who drink de-mineralized water (hypotonic) over a long period of time tend to be more prone to degenerative diseases such as osteoporosis. Berkey® Purification systems do not remove all of the beneficial minerals from the water, but they do extract harmful heavy metals such as lead and mercury as well as sedimentary minerals such as iron oxide. Therefore, the TDS reading will not typically change much unless there are a lot of heavy metals or sedimentary minerals within the source water.


Pathological Removal Capability of a Reverse Osmosis System


Reverse Osmosis does not remove pathogenic bacteria and that is why it is often necessary to add an additional UV light to the system. However, the UV sometimes does not kill all the bacteria because any turbidity in the water can create shaded spots, preventing some bacteria from being exposed. Typically, the UV is installed before the bladder tank; however it is in the bladder tank that bacteria usually colonize. Therefore, if the bladder tank is not sterilized on a regular basis, it becomes a source for bacteriological contamination that is never exposed to UV. Additionally, the carcasses of the dead bacteria remain within the drinking water with a Reverse Osmosis system, whereas they are removed by the Black Berkey® Purification elements.


Tankless Reverse Osmosis Systems


While some newer tankless Reverse Osmosis systems have overcome the issue of bacteria colonizing in the bladder tank, these systems have their own set of inherent issues, including:

  • TDS Creep:  without a flush tank, the initial water coming out can taste horrid, due to increased TDS in the water.
  • High Failure Rate:  some tankless models have already been removed from the market, due to numerous issues, including high rates of failure.
  • Noise: depending on the specific model and features, some units are extremely noisy to operate.
  • Excessive Water Waste:  this is a problem with both standard and tankless Reverse Osmosis systems.
  • Cost: with multiple membranes being used, the overall cost per gallon, can be even more expensive than older style Reverse Osmosis systems.




Reverse Osmosis systems typically are the most expensive due to the cost of the system and the additional expense to have the system plumbed in. Next in cost would be a Distillation unit. A Berkey® system will typically be the least expensive of the three. With respect to cost per gallon of water, calculated upon the cost per gallon for replacement filters and energy costs, Distillation systems and Reverse Osmosis systems that are properly maintained typically cost between 35-65 cents per gallon. A Berkey® system typically costs about 1.8 cents per gallon.




Reverse Osmosis systems can have up to four filter elements, with each needing to be changed at differing intervals from four months up to two years. This requires that the water pressure be shut off and part or all of the system be disassembled for maintenance. Additionally, the bladder tank should be washed with a chlorine solution at six-month intervals to kill any colonizing bacteria. Distillation systems need to be soaked and cleaned with vinegar solution to remove the scale, typically after each gallon or two. All Berkey® systems are easy to disassemble and clean. Typically the lower chamber should be washed in ordinary dishwater once per month.


Beneficial Minerals in the Water

Reverse Osmosis systems strip out the beneficial minerals from the water making it an acidic, “hypotonic” solution. A hypotonic solution is a de-mineralized solution. This ultimately has impact on the body because when a hypotonic solution comes in contact with a hypertonic (mineralized) solution, equilibrium is sought. The hypertonic solution in this case is your body’s fluids which are full of minerals. Continuous drinking of a hypotonic solution results in minerals being transferred from your body’s blood and lymphatic system to this de-mineralized water and being flushed from your body. Over time, in an effort to re-mineralize itself, your body will begin to rob it’s organs and bones of these minerals. This continuous cycle will have a negative impact on bodily function unless there is sufficient minerals being taken in through food and supplements to counterbalance.





The black berkey filters that come standard with all our berkey water filter systems are purposefully designed to leave the beneficial minerals in the water to avoid this dangerous cycle of body demineralization.


On a related note, the large majority of the population does not get sufficient minerals from their food because it is nutritionally depleted. No matter what your source of water, or filtration choice, we recommend a high quality multi-vitamin and/or mineral formula on a daily basis.  We stress high quality because many supplements on the market are created with low quality ingredients and are not designed synergistically, and thus are not absorbed or utilized by the body beneficially.


Pathogenic Bacteria Removal


Reverse osmosis systems DO NOT remove pathogenic bacteria like e-coli and giardia. This is the reason why many reverse osmosis systems include an ultraviolet (UV) light designed to kill the bacteria. Sometimes however, if the water has a high turbidity, shaded spots in the water can prevent some of the bacteria from being exposed and killed. Also, if the UV light is installed prior to the bladder tank, it can allow for bacteria to colonize in the bladder tank itself. If this tank is not sterilized often, it becomes a source of bacterial contamination. One other important note is that the remains of dead bacteria remain in the filtered water of RO systems that use a UV light.

The berkey water filter removes the pathogenic bacteria to a log 7 degree and keeps it out of your drinking water. Log 7 equates to a 99.99999% bacteria removal rate.




The installation of a reverse osmosis system is not terribly difficult, but you would want someone relatively handy or with some plumbing knowledge performing the job. Some companies will do this free of charge, and some RO systems are DIY.  It will depend on the size of the system, the company, and any contract that is signed.

The Berkey system DOES NOT require any expertise and is meant for the lamen. Upon receipt of a Berkey, total priming and assembly time is approx 10-15 minutes. The Berkey is standalone and works independently of your plumbing, so you can setup and move the system where you desire.


Cleaning and Maintenance


Reverse Osmosis systems typically have up to four filter elements, with each needing to be changed at differing intervals from four months up to two years. This replacement requires that the water pressure be shut off and part or all of the system be disassembled for maintenance. Additionally, the bladder tank should be washed with a chlorine solution at no longer than six-month intervals to kill any colonizing bacteria.

The black berkey water filters last 6000 gallons per set of 2 and typically 5 years or more before replacement is needed. The fluoride filter needs to be replaced every 1000 gallons every set of 2. As for maintenance, we recommend washing the lower chamber of the system with soap and water once per month.


Power Needs


An RO systems needs power to operate and filter your water.

A Berkey works via gravity, and DOES NOT need a power source. This is critical in times of an emergency or disaster situation.




A RO system requires approx one gallon of water for every gallon of water that is filtered.

A Berkey DOES NOT waste any water as part of the filtration process.  What’s poured into the upper Berkey chamber, is filtered into the lower chamber for consumption.




A typical reverse osmosis system costs 20-65 cents per gallon.

The berkey water filter costs less than 2 cents per gallon and since it does not require electricity, berkey filters do not have added energy costs.




Typically, the taste for the reverse osmosis systems can vary depending on if the specific systems re-mineralizes the water or not. So, it can range from almost no taste if the water is not re-mineralized, to the taste of the minerals that is being put back into the water.

The taste of berkey water tends to be very good unless there is an abundance of ionized minerals in the source water as the Berkey will not remove these. This is why we cannot guarantee a taste because not all source water is created equal and Berkey cannot control this. However, we hear daily from our customers about how much they enjoy the taste of their berkey water.




Obviously we are partial, but for the money spent, the Berkey filter is hard to beat.  If you have the space for the Berkey in your kitchen, etc, we think it’s a no-brainer for those who want the highest quality of filtered water at a low lifetime of use cost.