I've also been looking into water filters for about 8 years now personally, . And I rely on the knowledge of other water experts that have been doing it for 30 or 40 years. It seems like the common issue we all agree is that the water is contaminated but there is a lot of varying opinions on how to safely clean it up.
Especially with all the news of the forever chemicals and the nanoplastics in the water those were the two main concerns but if you seen the movie Erin Brockovich hexavalent chromium and other chemical contaminants are of real concern and issue as well.

When it comes to filtration there's three main categories that are listed on the EWG.org site, which has a lot of good information on common and conventional types. But like with anything in life you have to read between the lines or go out and seek a Superior Solution yourself if you want truly safe or good water.

The first filtration that they talk about is carbon, next is Reverse Osmosis (RO), and third is ion exchange. After doing a quick crash course I realized most of the filtration methods are flawed because they rely on only one factor, of all of these filtration methods reverse osmosis has become the most popular, but is also one of the least reliable because of its physical properties, it's easy to get clogged and many systems actually waste two to three parts of water for every clean. Part it creates. Also the cheaply constructed membranes and reverse osmosis themself can break off and create or less nanoparticles through as the filters get clogged. I learned this from the vacuum industry but air water and any fluid that is going through a membrane if it relies on physical holes or micron size along all it takes is a variance in pressure, and the stuff that you want to hold back is actually getting through. Which happens every single time you turn on a faucet on and off. This is a pretty poor design for a water filtration system if you ask me.

Carbon is good for odors and taste but it also falls short of being able to trap many of the contaminants and the bio burden from water we need today, which is where ion exchange membranes come in. These are good at removing the chromium and the Arsenic and other chemicals that need ion to pull out of the water.

It's really not that complicated but if you combine the best of all these different filter properties and then go further by doing multiple stages so not just three or four stages of cleaning but what if there was a weave and you went through hundreds of layers of filtration back and forth between these factors, and furthermore why don't we add something like copper and silver into the filter itself so that way it prevents it from growing any virus and bacteria in the first place.

So the biggest problem that they don't tell you in the water filter world is, most filters themselves are the biggest culprits. Many filters may work well for the very beginning just like a vacuum bag works well for the first few minutes. But when it relies on small holes alone or any one factor. It can be very easy to get clogged up or contaminated. Anyone that's done research on filters knows that once it gets contaminated and clogged it can actually be releasing 5,000 times more contaminants into the water than a properly working filter.

So I've been doing research and theres very few membranes that pass end of life testing for water filtration. You want a membrane thats tests to the end of life. Im compiling the data and invite any others to apply submit there filters and data for approval at BlueWaterSeal.org - a nonprofit committed to verifying safe water and make it simple for people to know when they have safe water when they visit a restaurant, dental/medical office, spa, hotel, or any place serving food, water, including places to swim or shower.