What are the must haves and do not really needs for an RO/DI Unit?

[mosesbrown]

I have been looking at these systems and see a lot of add on's and small (maybe not so small) differences between them as you go up in price. I do not want to break the bank, but I realize this is a very important investment in my tank and evolution in this hobby. What are the features I really want to have? Presure meter, TDS meter, Single DI, Double DI, back flushes, etc...

Thanks for helping make the right decision the first time:)

[AZDesertRat]

Must haves:
1. Dow Filmtec 75 GPD RO membrane or the Spectrapure hand tested variation of the same.
2. A prefilter in no larger than a 5 micron rating, smaller is better and an absolute rated filter instead of a nominal rated filter is best
3. A solid carbon block in no larger than a 1 micron ratings, 0.6 or 0.5 is even better as it will adsorb up to 20,000 gallons of chlorine and VOCs at 1 ppm.
4. A standard sized 10" vertical canister and refillable cartridge type true DI filter.
5. An autoshutoff valve if you intend to use the unit with a float valve, switch or pressure tank.
6. A handheld TDS meter. Inlines are good for indicators but are not as accurate as handhelds plus they are not portables so cannot be used to test tap water or other water sources like a small pocket sized handheld can.
7. An inline pressure gauge to help troubleshoot pressure and delivery problems.
8. A DI bypass valve so you have access to RO only water for drinking or other uses.

Nice to haves:
1. A drinking water kit so you can use RO water for drinking, ice maker and cooking.
2. A storage vessel for top offs and water changes controlled by a float or switch and solenoid.

[mosesbrown]

That was exactly what I needed know. Thanks AZDesertRat.

[Abynum1]

They should make that a sticky.

[mosesbrown]

AZ, I sent you a PM.