DIY DI filters

[oldsaint]

For less than 100.00 I can get 2 DI tanks, anode/cathode, filled with about 1.2 cu ft of DI resin. They're about 6"-8" round and stand 3'-4' tall. I use these tanks for spot free water at my car washes. They have ZERO waste water, filter down to 0 ppm and it makes about 2000 gals of water before it reaches 50ppm. This is the stoping point for what is considered spot free in the business. What's wrong with using this water for my tank. I could put a carbon filter before the first tank to remove any chlorine or chloramines, which would also extend the life of the resin.

What am I missing?

[wanareef]

Ro

[oldsaint]

Help me understand, if the reading is 0 ppm out of my RO/DI whats the difference in the reading of 0 ppm from just a DI filter.

[yardboy]

The RO removes 95% of the contaminents before it gets to the DI, therefore extending the length of run to the DI. That's all. Only other thing is not to let the DI run to 50ppm before changing them out. More like 1-2 ppm. Spotting requirements are not the same as tank water purity requirements. Other than that, go for it! Putting a carbon filter before it is a very good idea also, since the DI will not remove chlorine or organics from the water but the carbon will.