Which brings up the questions: How do you build one or where do you find the information to build one? I know the price from the company is $300.00, and I'd rather not spend that much for a filtration unit.

Also, what about the water filters you can buy pretty cheep for drinking water. The Britas, PUR, Culligan, etc?

Carl,

That is exactly what I was thinking.  I was going to say that earlier, but decided to let it go.

Adam

I think that my way's the cheapest:  Every couple of weeks we take our 5 gallon jug along with us to the petstore.  There we look at the fish and stuff, fill up the jug, and use it for the next couple of week's topoff.  Works great for a little tank!

 Brian

Aren't we talking about make-up water here?  Can't use NSW.

Mark, I've given my reasons in past threads why I prefer RO/DI over cold sterile.  There is no easy way to tell when your cold-sterile filter material goes spent.  And there's too much magnesium, imo, in tap water.

Doberman, those cheap drinking water filters are usually just a particulate filter followed by some activated carbon.  They just remove smells and taste (organics).

In many process outside of RO (since they are generally all plastic and elastomers) one can usually find traces of metals since they are often not a concern in most applications.  This is especially true in other technologies like distillation processes.  But IME, metals are not usually in the final product of DI. It's pretty much sterile.

What is Deionization? The deionization process removes all ions from a solution. Cation exchangers remove all cations (positively charged ions such as Sodium, Calcium, and Magnesium) and anion exchanger remove all anions (negatively charged ions such as sulfate, bicarbonate, and chloride). The cation exchanger is operated in front of the anion exchanger and converts the salts to acids.

CaSO4 + 2R-H CaR2 + H2SO4

NaCl + R-H R-Na + HCl

The anion exchanger removes the acid from solution:
H2SO4 + 2R-OH R2SO4 + H2O

HCl + R-OH RCl +H2O

The result is water without ions. Some Sodium will leak from the Cation exchanger and this is what determines the purity of the water leaving the system. One ppm Sodium is equal to 5 micromhos conductance (or 0.2 megohms resistance).

Mark, I thought that this was pretty interesting from PBM's website. I know that we have discussed retroing RO to KS before...

I have several filter canisters, at home, can someone
purchase just the media and attempt to make their own
Kold Ster-il� System?

No! First, the Kold Ster-il� System is a U.S. Patented Product. Second, the filter media are subject to separate U.S. Patents. Poly-Bio-Marine, Inc.� will not allow it's patented media nor patented internal media retainers to be used in any other systems or canisters without a license and proof of product liability insurance. Finally, the addition of the Kold Ster-il's three filter media to any other filter canisters ---- is a waste of time and money. Our Patented filter media will not function in any other canister system ---- without the Patented (Filter Media) Retainer Assemblies. Poly-Bio-Marine, Inc.� did the research & development before applying for the Patent on the entire system and as such is protected under federal laws from: reverse engineering, usage of media in any other nonlicensed systems, and any pseudodesigns, copies, clones that attempt to make similar performance claims. The Kold Ster-il� System is the only system using 10" canister capable of 14.0 liters per minute and meeting Japan's 46 item drinking water certification.

Carl wrote: dehydrated water is the best alternative.

To re-hydrate it, do you just add water?

I have read that with di water, there can be copper traces due to the spiral tubing used in some di processes????

Repto, I think you're thinking of distilled water.  Distilling may use copper coils to condense the whiskey... err I mean water.  But more typical nowadays are glass condensers which obviously don't release copper.

(edit:  ya what shane said...)

I think that highly processed dehydrated water is the best alternative.

You must think like the guy who started this venture:  http://www.thehawaiichannel.com/money/3005324/detail.html - http://www.thehawaiichannel.com/money/3005324/detail.html

$33 for a bottle of desalinated Hawaiian deep sea water   Those kooky Japanese .

I wonder what we could get for desalinated GSL water?

I have been successfully running 2 tanks with tap water. Tank 1 for about 8 months now and tank 2 for 5 months now.

Tank 1: This tank has been on tap water only, for about 8 months as I said.  It has a protien skimmer and a fluidized bed filter in the sump.  I am running 5 55-Watt PC's.  2 10K, 2 actinic, 1 50/50. I had very little algae problems in this tank until I refilled the fluidized bed filter.  (It was used and had very little bed in the filter.  When I got the right media I filled it full.)  At this time the algae started growing on the glass very rapidly.  I had to clean it every other day just to have visibility.  After 3 days of no cleaning you could not see through the glass.  I learned that Fluidized Bed Filters needed at least 3 months to really "Kick In" so I decided to give it at least that long before doing away with it.  At the same time my Protien skimmer quit working.  I have since fixed the protien skimmer and the Fluidized Bed Filter has had it's 3 months.  I now have far less problems with algae although it still grows on the glass and must be removed weekly to keep it pretty.  I don't know if the algae problems I now have are due to the tap water or not, but I suspect that they are.

Tank 2: I just changed tank 2 to RO/DI 2 weeks ago.  Although I have not noticed huge amounts of algae growing in that tank while using tap water I have had low lighting on that tank until 1 week before the change to RO/DI When I added 2-250 watt 20K MH HQI's.  This tank also has plenty of caulerpa in the refugium and maybe this has been the difference.  I will say that there are several patches of cyanobacteria that have been everpresent in this tank since it was set up.  No matter what I do to remove it, it always comes back in those small areas.  I will keep an eye on this tank as more and more of it is changed to RO/DI water through top off and water changes over the next several months.

The calcium in these 2 tanks has always been at least 350 ppm even though I haven't added any except what comes in the tap water.  I figure I will have to start adding it to tank 2 now that RO/DI is the only water being added to it.  I plan to continue using tapwater in tank 1 for the forseable future so I will continue to keep on eye on that one as well and see if I can see any differences in how the two tanks get along.

I don't know if this is the kind of info Mark was looking for or not, but I thought this might be helpful.

Either is ok.

Some of the DI cartridges are not NSF-PW tested for potable water so manufactures suggest they not be used for drinking water... but you're most likely ok if you do.  I drink DI water at work often.  And I haven't noticed any side-effects... any side-effects... any side-effects. 

At home, I'm a tap water kind of guy (even though I have RO/DI there too).

Well - I only drink RO water - tried the DI water once and thought it was disgustingly bitter. On most of the diagrams for installs it shows the drinking water faucet to come off right after the RO filter and before the DI. Sometimes water is taken from after the DI, but only if it first went through another carbon filter.

Most of the sites warn against drinking DI water - is this because of taste or is it actually unhealthy?

DI water isn't healthy or unhealthy... it's just water.

You can buy drinking water cartridges that contain carbon and a mixed DI resin.  They're expensive and don't last long, but they're considered safe.  I really think the reason why RO/DI manufactures warn against it is liability since the DI cartridge hasn't been given the stamp of approval from the NSF or some other agency.  And it really isn't needed, imo.  The reason people use water purifiers is to remove harmful compounds from the water such as arsnic, lead, iron, ect...  RO is plenty good for that.  If taste is the issue, most times carbon is sufficient all by itself.

Others may have other opinions...