Diy Cati Ani

[thriceanangel]

Does anyone think that it's possible to use my current fairly standard RO/DI unit and make it use the Cation and Anion replacements from this?
http://www.petsolutions.com/Deion+200R-I-51900142-I-C-44-C-.aspx

 

[guido_kp]

how come? your rodi already has the anion/cation material in it probably just all in one canister. it looks like it would be alot cheaper to get a couple upright filter canisters and some di resin if you want to upgrade the one you have. that one you linked to doesnt make sense - i dont see a ro filter - that means the di resin wont last long at all. at that price, it'd better be re-chargeable. which is a whole new can of worms using hydrocholric acid and sodium hydroxide.

or you just want to use the replacement resin?

 

[thriceanangel]

I guess to answer that I'd have to explain all about the differences of RO/DI and Cati Ani. There is no cation anion material in a ro/di filter. It's filtering is done via a membrane. The DI does have limited ability to remove some ion material, but not nearly the quality of cati ani. Make no mistake this isn't a deionization filter. It is what people who traditionally have to change many hundreds of gallon of water use in many cases, and something that has also been promoted by people like Anthony Calfo.

The biggest reason I want a Cati Ani is the fact that there is zero waste water produced. There isn't a constant stream of water being rejected by the RO membrane. And if I can use my RO/DI filter and retro fit it to use the cation and anion material, I will definitely do it. Not only that but the resins can be regenerated too.

 

[A.T.T.R]

yes you can doit
but buy it from spectrapure.. bulk sizes.. i think a gallon is like 60 bucksd

 

[manderx]

There is no cation anion material in a ro/di filter...The DI does have limited ability to remove some ion material, but not nearly the quality of cati ani. Make no mistake this isn't a deionization filter

you sure about that? you might want to read up on it from more informed sources. i bet there is a legitimate article linked in the stickied thread in the chem forum.

what you are calling 'cati ani' (wasn't that just the brand name for one made by aquamedic years ago?) is just a separate bed di. the di stage in your RO/DI is the exact same stuff, just mixed into a single chamber (mixed bed). straight di will not make water as pure as ro/di despite what some 'experts' who push DI over RO/DI believe. there was a great thread here on rc somewhere by him where he said everyone running ro was stupid. then when a few people in the thread followed his advice and converted, they had problems and were greatly dissatisfied with it. he didn't seem to understand that di performance is tied directly to tapwater tds. if you are lucky and have really low tds out of the tap, then it might be worth looking in to. if i lived in BC i would think about it. i think i've seen some people there say they have <10 straight out of the tap.

plus (to get to your question specifically) the standard filter housing on your RO will not hold enough resin to make enough water between refills to be fun. depending on your tapwater, you might only get 25 gallons before having to swap in fresh/recharged resin.

and even if your tapwater is soft enough to be worth doing DI only (and you don't care that it isn't as pure as RO/DI), then you still have the pita of recharging the resin with nasty chemicals.


resindepot has bulk prices and lots of info on it. if i was gonna make one, i'd think 4" tube x 36" tall for each chamber at the bare minimum, preferably 6". use your old 10" filter housings for sediment and 2 carbons to prefilter before going into the di stages. if you aren't into working with acrylic for something pretty, you can use PVC since there's no need to see in.

 

[Icefire]

Like manderx said, DI in RO/DI is a mix of cation/anion DI resin.
straight tap will use all the resine fast and cost a fortune.

Want low waste ration? use 4x RO membrane and a booster pump to get 1:1 ratio.

 

[thriceanangel]

From Calfo:

DI units used to be rather common but RO units for drinking water are so cheap and massively produced that they have blitzed the aquarium industry. But the quality of these units overall is rather mediocre at best (defined by poor reject ratios of 4:1 or worse versus professional/lab units that are 1:1). Really... they are a wasteful, inefficient wat to produced demineralized water IMO.

You can buy seperate bed resin (two column... cation + anion) DI units with or without RO units. When the latter, my advice is to strip the RO membrane and sell it off or give it away. You will save far more money this way for not wasting (reject) water that must be passed for using the RO unit.

Do note that not all resin is equal. There are many different grades, prices and product water qualities. Sadly, many of the aquarium brands use really cheap resin, or worse... they mix the resin in one chamber so that you cannot recharge and recycle it. Shameful [Sad] Or at least wasteful IMO.

.

Anthony Calfo

 

[manderx]

like i said, try to find some more informed sources. he doesn't know what he's talking about.

 

[thriceanangel]

I think he's pretty informed being that the number, and quality of articles, books, and sheer reference material outnumbers anyone else here (at least in THIS thread). No offense but I'd take his opinion over yours simply because he is the one I see invited to give talks by large groups of knowledgeable reefkeepers, public aquariums, MACNA etc.

Not too mention his own coral propagation farm

 

[douggiestyle]

there is much more to making a decision on what is best.
for instance what is you water tds before filtering. one with very hard water may find that a di cart does not last very long. also one would need to be willing to work with smelly and very hazardous chemicals for recharging. is the waste water from a ro being being wasted? how much is water in your geographic area?

as you can see, many people will have different situations. so its not a "one size fits" all solution.

 

[thriceanangel]

My water bill has jumped almost 100% since adding the RO/DI. I have decent water- TDS around 30-50. Its municipal water. The chemicals aren't all that hazardous- drain cleaner & HCl. Mix them and you can drink it. I'm not sure it's the answer, but like most things that are in tis forum- worth a try, if for no other reason than to stop the waste. If I can get a decent amt of water before recharging- it may be the way tp go. I just wanted to know if a std RO/DI system could be used this way.

 

[douggiestyle]

they are hazardous chemicals. cant do it in the house, the wife thinks they smell bad. cant do it around my kids. many would never play with them period. i play with them. i recharge my carts. ive also had hazmat training and worked as chemical mixing technician. my water is similar to cement. so like i said its different for each person.

if your water bill 2x after adding a ro i bet there is something wrong. unless, your previous water usage was flushing the toilet once per day. what is your top off requirement?

 

[Conesus_Kid]

Thrice: sent you a PM

 

[thriceanangel]

got it. Replied

No there was an increase in water costs. Plus its used for drinking water, and baby formula etc. My top off WAS a gallon/day give or take, but now I have downsized and is far less. Plus there are a few other things- like having a baby that has added a few more wash loads. But trust me there is nothing wrong with the RO, just 4 gallons going down the drain for every gallon I use. A couple 20 gallon water changes, filling a new tank, sump leak malfunction, on top of normal usage which has gone up. Turning my 200 gallons RO water into a 800 gallon bill- a real waste.

 

[bnmir]

DI

DI

Deionization is capable of making massive quantities of ultrapure water. It's commonly done in industrial settings.
I used to work in the semiconductor electroplating industry, and we had DI columns about 1 story tall. They regenerated every few days, microprocessor controlled, feed pumps, fully automated. We're talking mega-ohm resistances here.
Mechanical filtration, then carbon, then DI (separate beds).
No reverse osmosis whatsoever. We briefly had some problems with colloidal silicates passing through the beds, if I recall correctly.
By the way - muriatic and lye aren't any more dangerous than many household or pool maintenance chemicals.

And I have it on good authority that someone will be importing the Kati-Ani brand units to the US again shortly.

 

[AZDesertRat]

RO is Reverse Osmosis or a membrane system usually preceded by a sediment and a carbon filter. RO/DI is the same only it is normally followed by a mixed bed cation anion deionization cartridge so RO/DI does have this.
DI resins can be regenerated if they are kept seperate and not mixed but it is not worth the trouble in most cases. You will also have trouble getting the right blend, no mixed bed DI resin is a 50/50 mixture so you would have to experiment with the correct blend or your pH will be affected. Resin is cheap and if its used after a good 98% rejection rate RO membrane it lasts a long long time.
Other things to consider is you will never recharge it back to 100% efficiency, that requires heat and conditions you cannot provide at home. To get an idea on how long factory fresh resin will last, 16 oz or 1 pound of mixed bed resin will treat approx 2000 total TDS. A standard 10" vertical refillable DI cartridge holds 24 oz of resin so can usually treat 3000 total TDS. If you have a tap water TDS of 60 you can expect 50 gallons of decent water. I say decent water as there are constituents that DI is not good at removing on its own just like RO membranes are not good by themselves nor is carbon. It takes all three.

 

[Icefire]

Like I said, make a system with 4 RO membrane, you'll get 200g good for 200g waste.

It will cost 3 housing and 3 membrane with some tubing. Maybe a booster pump.

Way cheaper that buying/recharging resin...

Calfo may be good with reefs but he know no enought about RO water. AZDesertRat work in the field.

 

[scottras]

Waste water from an RO unit is only wasteful if its wasted. I run my RO waste into my washing machine. Soon I will have it plumbed into a rain water tank that will be used for the washing machine and toilets.

 

[Icefire]

There is also the Permeate Pump which save 80% of waste water and boost tank pressure.

http://www.moseswater.ca/pump.html

 

[redox]

did someone say mixed bed resins CANT be regenerated?Well they can. I have seen it done many times. The beads are seperated by weight. the lighter resins are seperated out of the mix when fluidized then each resin is regened with the apropriate chemical and the remixed. Each time you loose some capacity due to the fact that not all the beads might not have been seperated durring the first step. If you want a homemade cati-ani setup just simply buy a cube of cation resins and a cube of anion resins and keep them in two different mineral tanks. The mixed bed resins are more effective in tds removal than the two different bedsthe cation resins cost less than 100$ for a cube and the anion are about 200$ for a cubic foot. Im not sure why anyone would pay all the money they want for that Kati-ani system when a diy is cheaper and for a larger volume. A 2 cubic foot cati-ani system that is capable of large volumes of water can be diyed for less that 400 bucks. This includes 2 polyglass mineral tanks