Tap Water Filter VS RODI System

[9kin]

Please help me answer the following question that arose today. I have a 5 stage 150 gpd RODI system that gives me 0 TDS (which i paid $270 for)http://www.airwaterice.com/c=hyQ6iB...RODI-with-Gauge-TDS-Alarm-Dual-TDS-Meter.html.
Today out of curiosity i went to my brother and tested his water coming out of Tap Water Filter (very small and simple device for $50) http://www.marinedepot.com/Aquarium...icals_API_MARS_Fishcare-AP4111-FIRODI-vi.html

And to my amazment that water came out to be 0 TDS. I am baffled by that discovery and trying to figure out why RODI systems are better. All i hear about good water is 0 tds and no other parameters, however both devices giving me 0 tds.

What am i missing?

 

[KathyC]

What am i missing?

That your 'real' rodi will process many, many, many (did I say that 3 times? ) more gallons of water and still have a TDS of zero, while he will need to replace the cartridge portion of his a LOT more frequently than you.

 

[lfsmarineguy]

Was going to say, those tapwater filters can only produce MAYBE up to 20gals per filter depending on the source water. That's going to get expensive fast if you really think about it.

 

[jrobbins]

i use the api tap water filter and have for years. i get about 200-300 gallons per filter. i also live in nyc and the tds in my source water is only about 12ppm. YMMV

 

[NewfiDog]

That filter is just a DI filter, thats why you get the 0 TDS but it will not remove other things the RO will remove first such as chlorine.

 

[9kin]

Thanks. Now everything makes sence.

 

[Jzhou]

i'd suggest the API tap water filter if your living conditions won't allow for a rodi, but the rodi, is alot better