What is the difference between RO/DI water and distilled water?

[Damsel13]

I think I have asked this before but I still don't understand. Could someone give it a shot explaining this again?

 

[mmkeeper]

My best guess is that they are same as in TDS but get there thru different means.

 

[mmkeeper]

Try this link. http://fins.actwin.com/killietalk/month.200104/msg00426.html

 

[Damsel13]

thanks mmkeeper and I nuked the aiptasia YAY!

 

[Jobiwan]

Distilled water is pretty much guaranteed to have 0 TDS, RO/DI varies according to the condition of the filtration elements, which is why RO output has to be tested for TDS to determine when the membrane needs to be replaced...distilled is more expensive to produce, uses more energy to obtain, hence is less environmentally friendly....

 

[Damsel13]

thanks Jobiwan I am getting a clearer picture. So it is less "green" as you said less environmentally friendly. Well my car is little and gets good gas mileage so the small amount of distilled water I use is a trade off.
Thanks so much for the answers.

 

[Kurt_Nelson]

I'm not sure I'd make the distinction that distilled is less environmentally friendly. Granted, it does take more energy to make it, but with RO/DI you're getting 1 gallon of "pure" water for every 3 to 5 gallons that you're putting in. Granted... you can reuse that waste water for something else, but I bet most folks just put it down the drain. There's also the chemical issues of making the RO membranes and the DI resins.

Not sure how to compare energy versus wasted water/chemical byproducts, but to me it seems like neither RO/DI or distilled is really earth-friendly.

 

[Damsel13]

Things to consider...hummmm. That is why I love this site. Always keeps me thinking. That is no small feat! LOL Usually I go with my gut instinct.

 

[Scooterman]

It does take a lot of energy to convert water to steam but also takes energy to make membranes etc & there is some waste, I usually suggest the duel 75gph RO units because of this, the waste of one feeds the second unit thus less waste & almost three times the output of the single RO units.
Then If you want green, consider the pumps & lights we run, all consume lots of power, pumps that run 24/7 actually can use more energy than lights because they never shut off, all to be considered, I've tried to get the most out of my equipment as far as energy savings, although it still isn't cheap.

 

[Jobiwan]

Ouch, good point Scooty, you are absolutely right, I'm staying off this thread now, I don't want to think about how environmentally unfriendly our hobby is, bad enough trying to hide the electric bill from my spousal unit....