Reverse Osmosis Filter - Pros And Cons
I just set up my new reverse osmosis water purifier a couple of days ago. It purifies water from most organic and inorganic compounds and elements, creating what's called 'permeate' - water that is devoid of minerals.
Water filtered by reverse osmosis needs to be remineralized to be deemed healthy and acceptable to drink.
There are several reverse osmosis filter options on the market that use different mechanisms to remineralize purified water. My countertop filter has a post-filter that puts minerals back into the water after the water has been purified by the reverse osmosis membrane. Some other brands of filters sell mineral cartridges that add trace amounts of minerals back into the water after it has been purified.
Pros and Cons
I've been filtering my water through a Brita pitcher filter for the past five years, and it has done a good job. Brita pitchers use a carbon filter that is effective at reducing some metals and elements such as chlorine, mercury, and zinc. However, they do not remove organic contaminants such as bacteria or viruses. Most of us don't have to worry about organic compounds because our tap water is usually sufficiently chlorinated to reduce them to a safe level.
Despite the recent story in the news about the brain eating amoeba that a woman contracted through her tap water in Seattle, I'm not too concerned with live matter in my tap water - that news story sounds like a freak accident. My reason for getting a reverse osmosis filter is to reduce possible heavy metals and other elements such as chlorine and flouride.
To be fair, I haven't tested my tap water for heavy metals, so I don't know to what degree my tap water is impure, but I do recall a time when my tap water was brown with rust and other particles, so I think it's reasonable to take precaution against consuming garbage like that.
Although my Brita filter was fairly effective at filtering out most contaminants, it's not nearly as effective as a reverse osmosis filter. A standard Brita pitcher might remove up to 80% of chlorine from your water, and that's when it's in top working order with a new filter cartridge. A reverse osmosis filter reduces chlorine by up to 95% as well as most other compounds by close to 100% and most organics by 98%. The Brita pitcher is not certified as being effective in reducing levels of lead for example. I have old pipes in my building, and to say the least, the quality of the water coming through the tap has not been consistent, so to me it was a no brainer to invest in a better water filtration system.
In short, the pros and cons:
The reverse osmosis filter is one of the best solutions for purifying water while not completely stripping it of beneficial minerals (when equipped with a remineralizing post filter - as I have in the filter I bought). It gets rid of most contaminants and trace elements that other filters don't get rid of.
It takes less than 20 minutes to produce a couple of litres of purified water and has a 50% efficiency (meaning it effectively filters 50% of the water you feed it, and the other 50% gets put back into the collection tank). It's fairly fast and efficient and easy to maintain.
The only negative is that it sets you back over $500 for the system with filter replacements costing roughly $100 a year on average (pre-filter, carbon filter, and post-filter once a year for $66 and reverse osmosis membrane every two years for $66). Average that out for a 5 year span and it's roughly $200 max a year for a constant supply of purified water without the hassle of installation.
I'll keep you posted on how this thing performs over time.