RO systems are nice but not for every one…people with high water costs will be effected the most…with RO water you have waste water…its usally 2 gallons of waste for 1 gallon of RO…I used 2 RO systems when I had salt water reef tanks…i used the waste water to water the garden…but then switched over to mixed bed Ion filters…no waste an cleaner water…I was able to clean the resins using an acid…I have well water so was not worried about a lot of bacteria like in city water…I have my water tested every 3 years…always pristine with a little iron is all…but if on city water RO is the way to go if your water is bad…a simple activated carbon filter works if you just have a bad taste problem or a smell…forgot to mention…mixed bed filter will not remove bacteria or chemicals…just minerals…
Ok, once a year for the cheap filters. No Problem.
Didn’t know anything like this was available. It’s cheap too, so I may have to get one.
I changed the membrane recently, and the water is so much cleaner now at my new place, I don’t think I’ll have to worry about it for a while.
Glad I could help! 
I bought one of these, THANK YOU…I hate periodically testing with an offline meter. I havent looked for one of these in years. Last I did they cost a fortune.
Yea I remember installing them back in the day when I first got started in water quality, it really is amazing how the internet has changed things, you know I’m a plumber and I get worse pricing from my local suppliers than I do from the internet and I’ve been buying from them for going on 20 years, heck sometimes I get better prices at the big box stores.
I hear ya on that !
Not plumbing stuff, of course.
Oh, what is it that you do?