Sediment and carbon filters have nothing to do with final TDS, they protect the RO membrane so it lasts longer and works better. This is why Spectrapure systems last so much longer, give you lower TDS and cost less to own. I'm over 5 years on my present membrane using Spectrapure replacements and even stretching their schedule a lot. I am sure you have heard of Randy Holmes Farley; He reported 10 years on a Spectrapure membrane still at high rejection rates before replacing it. There really is a difference and its the complete package, sediment filter to DI resin and every thing in between. You get what you pay for and I would never go back to anything else I have ever owned and tested in the past. You can use a god membrane or good DI resin but if you do not protect the well with good sediment and carbon filters and a good, properly sized and trimmed capillary tube flow restrictor and monitor what is going on you are wasting money. Yet another time, there really is a difference.
I have not had that experience with the AWI array. You are correct,spectra pure makes a great product. Yet I have been getting 0 TDS indications with inline and hand held meters. I do use a spectra pure membrane and their DI and also use two add on DI's so most likely I would see the same results regardless of the brands of filters. IMO only
Am I reading this correctly... you have three DI cartridges (or whatever they're called)? If so, why so much DI? What is your TDS post membrane and pre-DI?
Am I reading this correctly... you have three DI cartridges (or whatever they're called)? If so, why so much DI? What is your TDS post membrane and pre-DI?
Tom
I use the large cartridge dual DI,I would like to explain but I am sure that it"s wrong too! I am running off a well and usually see a 400+ tds comeing into the unit.Sorry but I am going to bow out of the RO subject now.Just not worth it.
Dual DI is a good investment as Binford pointed out, especially if you have high TDS or unusual water conditions. If you use the same resin in both canisters you test the TDS from each individually and when you start to see any TDS out of the first cartridge you remove it, rotate the second cartridge into the first position and add a new cartridge in number two position. With long bed residence time you get 0 TDS treated water and long DI life.
Another common version of dual DI is Spectrapures MaxCap system where their Max Cap resin goes in first position and something like the SilicaBuster or any nuclear grade resin goes in the second. You will replace the MaxCap on average 3-4 times before ever seeing any TDS from the downstream SilicaBuster cartridge and replacing it.
Please excuse me for doing this but here is a thread from another forum explaining how it is different from most RO/DI systems: