DI w/o RO?

[4Texans]

I would like to try pre-treating my water with DI but without RO.

I can not seem to find any units that are sold this way.

The following seems ideal to me:

A unit with two clear canisters and one op. then I could run
- Clear unit 1: Pos ion color indicating media
- Clear unit 2: Neg ion color indicating media
- Opaque unit : Carbon

The idea is that the clear units hold rechargable media that change color when they need to be recharged.

I can not find:
- A unit like I described
- rechargable media (all pos ion, all neg ion)

So who all has used DI only? Anybody seen a DI only unit some place?

[The Punisher]

From what I've read on here the DI will become packed too quickly and will have to be replaced way too often to make this a practical solution. Where I'm in school now they have a mock water treatment type plant set up like you're talking about (with seperate positive and negative ion units) but we filter the water through 3 or 4 pretty big carbon canisters before it hits the two DI units like you describe. The DI units are a little bigger than SCUBA tanks and they have lasted two years with very light use. I can't imagine smaller home type DI units lasting very long at all if used often. Just wondering, what is your reasoning against a RO/DI, almost everyone who has them loves them and they are dirt cheap nowadays.

[AZDesertRat]

The life of your DI resin would be nil, zip, nada. DI will only adsorb a certain amount of contaminants before it starts releasing it back into the stream. Thats why you get the TDS as low as you possibly can with RO before putting it through your expensive DI resin. If your raw water TDS is anything over maybe 20 or 25 you will probably only get maybe 100 gallons per refill and unless you have a cheap source of refills you are looking at $9 to $20 per cannister per refill. You will very soon surpass the cost of a RO unit and then some.

[4Texans]

Hmmm. The idea was to minimize waste water. I wanted to try this on a small scale before I move up to large (1k+ gallons) tank system.

Any recommendations for a unit reasonable to use for a really small tank, say 30 gallon tank. (Still want non-mixed, color indicating, DI resins but I would consider going for RO first.)

P.S. The water is quite hard here, so I guess the resins could be really short lived... (I do not have the TDS readings right now.)

I saw this one "Premium Series 100 gpd RO/DI System - $155.00"
from http://www.buckeyefieldsupply.com/showproducts.asp?Category=91&Sub=1

but it seems a little too expensive?..

[AZDesertRat]

If your water is really hard or has high TDS try to get a 75GPD RO/DI unit. They are more efficient than 100 GPD units and make your DI last longer. Color changing resin is not a very good indicator of DI life at all. A $25 TDS meter is far superior. Usually by the time your color has changed you are leaching contaminants into your treated water. Why are you set on seperate chambers rather than a mixed bed resin designed for your particular water conditions? You can get bulk resin from places like Resin Depot and custom mix a blend to suit your conditions.
Buckeye sells good affordable units as does www.airwaterice.com and www.aquaticreefsystems.com. I suggest steering away from some e-bay vendors as they have so-so if any customer service and moast use the less efficient 100 GPD membranes. If you can get one to respond to yopu they may swap membranes for no or little money and then they might be worth it. Most use the same housings and fittings so its the filters and membranes that you are paying for.

[Reefmaniac1]

A DI treatment, just by itself will burn out very quickly. You will spend a ton of money in replacement media. Go with the Typhoon III from www.airwaterice.com.

[jimdogg187]

Or call Culligan. I'm leasing a industrial sized rig for $21 bucks a month. All my lfs use the same one. I go through about 50 gallons a week. The tech said my DI unit will 30-40 weeks before a recharge. Recharge is $115.00. It sounds pricey, but no maintanace, they deliver and it pumps out water on demand. No waiting, no need for a huge tub to fill during the week. When you want water, you get it. Fast. Jim

[Reefmaniac1]

So you are spending $367 per year on rent and maintenance...that's at least 2, quality RO/DI units, plus filter changes.

I don't store water in a huge tub. I have 3, six-gallon water cannisters that sit compactly in a closet and my RO/DI unit is plumbed into my sump for auto topoff.

[jimdogg187]

I was just making a suggestion . And yes, I think the money is worth it. And I don't call an RO/DI a quality unit. What I have is a quality unit. Jim

[Reefmaniac1]

Not criticizing...so please don't take offense. I was just analyzing the cost differences.

Why don't you consider an RO/DI a quality unit? If it's the "waste water" issue, there are ways around that. I dump the waste into my washing machine or use it to water the plants. So, there's no waste.

[jimdogg187]

Okay, my bad. There are quality RO/DI units out there. To be honest, I do 40 gallons a week in my FOWLR. In order to use a normal RO/DI unit, it would be time a space consuming. I would need to make the water in a big tub, heat it etc. I don't have the facilities for such a set up. I just want speed and ease. I just don't have much of either right now. Your right, an RO/DI unit is much more cost effective. No offense taken. Jim

[Reefmaniac1]

Cool. I can understand, now, why you chose that route. What works for one person, doesn't necessarily work for someone else. ;)

[rick s]

4 texans,

There is a re-chargeable deionizer. I use it.

Take a look at this thread.

http://archive.reefcentral.com/forums/showthread.php?s=&threadid=524634

[4Texans]

Anybody run just cation? Seems like most of the bad stuff would be filtered by a cation canister and would leave the good (water hardness, etc. and would leave some bad too)?