RO/DI alternatives

menelaos · Mar 25, 2013

I am closing on a new house and plan on setting up a 75gal reef. I curently have a 4gal nano with crabs ans snails witch i will combibne to start to seed new tank wich will be a slow process cause i droped all my loot on a new house lol.

I was looking into a RO/DI system but i work hard and budget very tight and cant stand that it wastes like 85% of the water i pay for. Is there a diffrent route i can go like just a DI or a cold sterile system that anyone knows of or has experience using that doesnt waste water.

Usctom · Mar 25, 2013

You can use the waste water for your plants or if you keep African cichlids you could use to change the water. There are ro systems that are less waste full but they also cost more.
If you were to use just di you would burn it up very quickly.

AZDesertRat · Mar 25, 2013

The DI only system is not the answer for most people as they are expensive to purchase initially and require hazardous chemicals and lots of water to flush and recharge the resin, plus you will never ever get the resin back to 100% condition at home.

The Kold Steril systems do not work as well as they would like you to believe.

depending on your water quality, meaning if you have soft water and normal to low TDS, Spectrapure offers several low waste alternatives starting at only $239. These range from less than 1:1 waste ratio to 2:1 or 3:1, all of which are more "green" than the industry standard 4:1 waste ratio.
http://spectrapure.com/email/Sale.htm

There really is no alternative to RO/DI with the possible exception of a small nano system where distilled water is a viable option since you use so little water

mcarroll · Mar 25, 2013

Well, there are home distilling machines, but either they batch produce only a gallon or so, or they cost into the 4-digits to get a high capacity model that could produce enough for our needs. I believe both machines mentioned are economical to run if they were to fit our volume needs better (i.e. there was a such thing as a mid-sized unit), but as the technology is marketed today they just aren't practical.

With exception to the high-carbon-footprint consumables, RODI is a very inexpensive way to get pure water. If you can be strategic with the waste water to get a good use out of it and not send it immediately down a drain, the pure water could cost next to nothing.

-Matt

AZDesertRat · Mar 25, 2013

Distillation units consume massive amounts of energy. It takes many many BTU's to raise the temperature of one gallon of wate reven 1 degree, most stills are 800-1500 watts and take hours to make a gallon. calculate that out and its prohibitive plus they require a lot of cleaning to get all the scale and minerals out so again, chemicals and lots of wate rto flush them out, not viable.

One big selling point of Spectrapures low waste systems is they are more "green". When you run less total wate rtrough the filters they last longer so do not require replacement as often. With their Select series RO membranes that are guaeranteed to be better than 98% efficient DI resins last many times longer so you send less to the landfill in the way of spent resins or cartridges. Very efficient and very green.

navila06 · Mar 25, 2013

kroger super market sells distilled water for 57 cents a gallon, if you dont have a kroger close to you, wal-mart sells distilled water for 87 cents a gallon

Mike J. · Mar 25, 2013

I do a couple things with my waste water. One, I fill up the washer. Two, only in the summer, I run the waste outside to a storage container and use it to water the garden and plants. I admit that I do waste a lot of water, especially in the winter. But, I use a lot of electricity, also. 1080 watts for lights and I'd have to figure out how many watts for pumps. Reef tanks are not a cheap hobby. A booster pump on your RO/DI unit will reduce waste.

menelaos · Mar 25, 2013

I see Maby ill look into one of those low waste ones, the waste and cost just gets to me otherwise. it will be awhile till i get it up ill be broke when i move in and want a dog real bad to lol. So i will see if anyoneelse chimes in but i will look into those for now thanks.

mcarroll · Mar 26, 2013

Don't be afraid to shop for a used unit....just be aware that a new set of filter media will be a large percentage of the cost.

Depending on the filter's config, as much as $80 or so for a whole new filter set. The beauty is that this set of filters will last you a lo-o-ong time (~600 gallons of product water wouldn't be out of scope.....could be more), and the ones that wear out the fastest are also the cheapest.

-Matt

AZDesertRat · Mar 26, 2013

Rarely is a used system a good deal. A new high quality membrane is $35-$50, a matched flow restrictor is $5-$6, a sediment filter and carbon block worth anything is between $16 and $25 and a new DI cartridge is between $18 and $25. A new reef quality RO/DI with a warranty and all new components including an inline pressure gauge is only $125. When the cost of parts to upgrade a system exceeds 50% the cost of a new system, not even counting the cost of the used system purchase, it makes no sense to me.