DI water only

[aiber]

Anthony,

Enjoyed your presentations at IMAC, greatly.

At IMAC you spoke about using only DI water b/c RO wastes too much water.

Can you please elaborate on that and possibly recommend links to places that sell DI only units that you recommend?

Thank you,

Albert

[Steven Pro]

Drs. Foster & Smith used to sell the Kati-Ani system which is a DI-only water purifier. Unfortunately, it appears they quit selling them. I just sent Aquatechnic (the manufacturer) an email asking if they have another US distributor. When I get a reply, I will post it here.

[aiber]

Thank you. I was really hoping that Mr. Calfo would chime in....Must be busy...

Thank you again!!

Albert

[Nanook]

Originally posted by StevenPro
Drs. Foster & Smith used to sell the Kati-Ani system which is a DI-only water purifier. Unfortunately, it appears they quit selling them. I just sent Aquatechnic (the manufacturer) an email asking if they have another US distributor. When I get a reply, I will post it here.

Thanks, Steven. I am looking into a DI only system for my 1200 gallons of saltwater coming soon. RODI is just way too expensive and wasteful for my pocketbook.

Dave

[Nanook]

FWIW, I am looking for the German resins and Kati/Ani systems for large water volume making ability.

Dave

[ktani]

I think that the last ones Dr. Foster/Smith had were sold to me.

After some learning (thanks Anthony) regarding the general instability of the water, it has been a flawless transition with 0 waste.

In a heartbeat I would do it again and hope we can find a source for the product here in the States.

Kip

[Anthony Calfo]

the zero waste thingy is very cool and conscientious

And DI can be (and often is) a higher quality than RO.

Many industries (plating, processing, etc.) that require high volumes of very pure water only use DI for its purity and (low) cost of production.

RO units have only been so popular in the hobby because they are an older (as in intro to the hobby) and cheaper (initial entry to the hobby) technology.

Times change.

DI is a better way IMO.

[aiber]

Originally posted by Anthony Calfo
the zero waste thingy is very cool and conscientious

And DI can be (and often is) a higher quality than RO.

Many industries (plating, processing, etc.) that require high volumes of very pure water only use DI for its purity and (low) cost of production.

RO units have only been so popular in the hobby because they are an older (as in intro to the hobby) and cheaper (initial entry to the hobby) technology.

Times change.

DI is a better way IMO.

Thanks for your expert opinion. Please supply with places I may go purchase a DI unit...

Albert

[Kathy55g]

Hi Anthony and all,
I was also at IMAC and was intrigued by the DI idea. I came home and found the places in Anthony's book to make sure I heard right.

What you do not mention is how to recharge the DI resin.

I bought my water purification RO/DI from a fellow reefer, and it did not come with a manufacturer's recommendations. Is there a recipe for doing this?

Thanks,
Kathy

[Steven Pro]

DI units that have the resins separated can be recharged with muriatic acid and sodium hydroxide, but most DI canisters for RO/DI filters do not have the resins separated. The kati resin is usually mixed with the ani resin making recharging impossible until the resins are separated. There are instructions for doing this online specifically for Aquarium Pharmaceuticals Tap Water Purifier, which is a mixed resin DI unit. Those same instructions should work for a DI canister, although one would have to keep them separate after the procedure for easy of future recharges.

[Kathy55g]

I tried to find this instruction on Aquarium Pharmaceiticals' web site and was unsuccessful. Could someone post a link?

Thanks in advance,
Kathy

[Steven Pro]

Originally posted by kmleah
I tried to find this instruction on Aquarium Pharmaceiticals' web site and was unsuccessful. Could someone post a link?

Thanks in advance,
Kathy

Aquarium Pharmaceuticals does not give the instructions. They want you to buy more replacement cartridges. Here is one online DIY set of instructions,
http://lgonzalez.net/aquatics/deionizer.html

[aiber]

Maybe I missed something but I have two questions and I hope someone can answer them...

1)Where can I purchase a DI only unit?

2)How do you recharge the resin?

If these questions are ingorant, please provide a link to help me out.

Albert

[Anthony Calfo]

Resins will come with recharging instructions if sold in separate columns.

Buying 2-column deionizers should not be so hard (they are very commonly used in industrial applications). But... the last big mfg for the aquarium industry has lost good distribution in the states.

Steve sent Aquatechnic (the manufacturer in Germany) an email asking if they have another US distributor. They apparently have not replied yet.

Perhaps you can/would do the same to remind them that there is strong interest in their fine product here in the US?

Also... look in some of the freshwater enthusiast mags/message boards, etc. The FW people that raise discus, killifishes, etc love to use DI only.

Anthony

[Steven Pro]

Originally posted by Anthony Calfo
Steve sent Aquatechnic (the manufacturer in Germany) an email asking if they have another US distributor. They apparently have not replied yet.

I still have not yet heard back, but as soon as I do I will post the reply here.

[overanalyzer]

Originally posted by Anthony Calfo
Resins will come with recharging instructions if sold in separate columns.
Anthony

What are the "names" or the types ofthe two resins you would need to use?

Thanks

[Steven Pro]

SpectraPure sells bulk resins,
http://www.spectrapure.com/St_replac_p5.htm

You would have to get someone to fabricate the reaction chambers, but that should be easy enough.

[Hobster]

Kent Marine makes a 200gpd DI only unit which can be recharged.

http://www.championlighting.com/home.php?cat=456

[fishdr]

would we be able to make our own modification to have a two part DI resin filter? I was thinking doing something along the lines of taking our old RO/DI unit and adding a second DI chamber. Then just filling the first DI chamber with one type of resin and the second chamber with the other type of resin.

Is there an order the raw water has to flow through?

Do you guys think this would work?

[WIKI2ECHO]

I too am sorry that I did not hear this talk by Mr Calfo. I work in a Research facility that generates 1000's of gallons of DI (18 megohm) water a week and that is after it passes through RO units. I dont have the exact numbers right now, but I am always being told how "expensive" DI water is to generate. It is NOT a (low) production cost item.
Secondly I cant imagine that we want to start storing and handling Muriatic Acid and Sodium Hydroxide in our homes. Looking more like an accident waiting to happen. Just my opinion.
I started my reef exactly like proposed. DI only .using 2 and 3 inline mixed bed DI units. This was NOT CHEAP!! My TDS prior to the DI was about 200 - 220. I was lucky to get 50 - 55 gallons of DI water that measured below 15 TDS before I changed out the filter.
Yes we do waste a lot of water with RO .and the " zero waste thingy is very cool and conscientious " but be prepared to spend a lot of time and money with straight DI systems besides the "safety factor" ..........unless there is some new Hitech DI system that I have not seen yet.

Just some Thoughts......Good dialog!

Bill

[leebca]

I too enjoyed your presentation (and show?) at IMAC, Anthony.

But the difficulty with DI is the quality. It is an admirable goal to want to use DI, but if the public water supply is such that the DI can't remove some of the offending ingredients, it is a frustrating and risky proposition to stick with DI.

My whole house is on a DI system with a salt recharging system. Added on to this is an RO unit which fills an 80gallon storage tank for my 'tank room.' I get a usual reading of 6 TDS from this water, no silicates, etc., etc.

The cost is about $10/500 gallons for the DI regenerator (the DI resin is guaranteed to me for a 'life time') and $100/15,000 gallons for the RO membrane. PLUS the wasted water.

The system is commercial and used by many of the electroplating firms others have posted about in this thread.

Although my city water is never in short supply (it is well water --- one of the worst in quality -- no rationing ever needed), it is about 15% the cost of the water in Los Angeles.

Although we should all be energy/conservation conscious, it's hard for everyone to enjoy driving around a Geo, when the 'Caddy' is only a bit more to operate, and safer.

[WIKI2ECHO]

Lee:
If you dont mind me asking....what is the "system Cost " for this house sized unit.

Bill

[Anthony Calfo]

Hmmm... I'm not sure what "expense" is being incurred by your industrial folks... but in my line of "work" dealing with huge freshwater, saltwater hatcheries/fisheries... running my own greenhouse (tens of thousands of gallons of water run through it)... I can say with real practical experience for having actually used and monitored DI systems that they are dirt cheap to operate and produce superb quality water.

I build a (coral-farming) business on it in fact (and a 3K gallon discus hatchery before it).

Lets be specific here:

A Kati Ani 5 (several pounds of resin) produced several thousands of gallons of water before needing to be recharged on the quality of my mains water. TDS on product water (no waste water) was single digits (always well under 10 ppm).

The cost to recharge it was 1/3 of a bottle each of Muriatic acid and Red Devil drain cleaner. Mere dollars per recharge.

For my GH (which fluxed 5-8K total gallons of water), I can't say that I ever spent over $30 per year on the acid and base to recharge my 2-column DI unit.

$30 per year!

No membranes to replace or fail.

And a resin that is nearly fully rechargeable and will not build up a "memory" to any significant degree in my lifetime.

The reticence to use DI is largely founded on unrealistic fears and from folks that have not actually used these units at home or have not seen fellow aquarists/fishrooms, fisheries use them so easily.

Muriatic acid is produced by the hundreds of thousands of gallons. Its in more home garages and basements than you might give a thought to (used for example to clean your tools).

Red Devil lye... come on! Its just drain cleaner. Is it dangerous? Sure. But so is extremely caustic Calcium hydroxide (kalkwasser). If you spill bleach or lye on your skin, it can burn you indeed. But if you inhale calcium hydroxide... you are(!) going tot he hospital.

So... along with pitching out DI and recharge chemicals, should we also throw out our Calcium hydroxide... and iodine... and jewelry cleaner... and gasoline from the shed...(you get my point)

On the danger scale... the acid and base chemicals for recharging DI are no worse (or less so) than many of the household chemicals you already have, or other reef additives.

And it is dirt cheap, easily neutralized and a fraction of the cost to operate compared to RO.

As for quality... again:

The majority of labs that I have studied or worked in are using DI (not RO). And it s not because it is cheaper to produce. Its for quality.

The real issue here is quality of the resin.

The resins used cheap hobby mixed bed deionizers versus industrial/commercial 2-column deionizers may be very(!) different.

Lets be sure we are comparing apples to apples here

[WIKI2ECHO]

Mr. Calfo:
In a way you may be right. Our facility has a cost of about $35/$40 per 1000 gal of RO/DI. when you factor the cost of materials and the labor to manage and monitor this system. Pretty cheap if you can get a 1000 gal of Hi quality 18 MegOhm water for $40.
In our case, when you multiply that by 2 million gallons per month...............we are talking serious money.

As far as safety I accept your point about bleach and iodine and drain cleaners. I do use Kalk and believe me I am EXTREMELY cautious when handling (and Breathing) it. Kalk IS difficult to handle.

Many of the people on this board may find many of the maintaince requirements of a reef to be a tedious chore already. If we are to add regeneration of Anions and Cations , I guess that it must be done in large enough a system so as to reduce the amount of times required to do so in the course of a year. In my case I was using 10" canisters of mixed bed and therefore changing them out every 50 gallons was becoming just another maintenance chore besides the expense.

Regards,
Bill

[Anthony Calfo]

spot on Bill

and very good point as well about the practical reality of reefkeeprs. Legitimately... many of us are already disinclined to even keep up with the (best case) daily cleaning of skimmer necks/cups for optimal skimming. With that and other necessary tasks... to add one more thing like DI recharge is indeed an inconvenience for some.

I just make the strong point above (and beyond) for those that are truly in need/desire for purified water. We have to pay to play, as they say.

Such folks will have to make the effort, and given to choose between frequent purging/backwashing of an RO membrane, the expense of its replacement and the somewhat variable quality of water produced (as the membrane ages and gets clogged before backwashing)... then the half dozen or so recharges per year at modest expense for DI with no placement costs is at least a wash on consideration. And really a better way IMO.

The other point not hammered on here is in regard to folks with really poor quality souce water. Such will be a burden on either RO or DI (more frequent backwashing/recharging). But DI always and only costs those few dollars per recharge... while frequent replacement of membranes for RO can be a staggering expense!

So for folks with really bad tap water... DI is a stronger candidate for its cheaper cost of ongoing operation.

FWIW

Anthony