RO/DI water question.

ckusnierek · 03-20-2007, 07:08 AM

Question 1:
My tap water is horrible here I have been going to the grocery store and buying 5 gallons at a time of "purified" water from the fill it yourself dispenser. At $.20/gallon I would rather go to the store once a week and buy water rather than pay 150-200 for a RO-DI system. Does anyone know that quality of water from those fill it youself system???? I test my water before and after water changes and it does not seem to be a problem.

Question 2:
At work I have a unlimited supply of DI water. Can I use just DI? Dosen't Deionizition remove all the nasty stuff and RO basically makes it taste better?

Thanks Alot
-Chris

abigtroutt · 03-20-2007, 08:04 AM

I only use RO/DI water for my tank. I would use the good stuff at work, as long as they let you.

Do you have a TDS meter? If so test both of them.

crvz · 03-20-2007, 08:21 AM

I think (emphasis to imply that I'm not certain) that a DI will remove all the same stuff an RO will, however the DI resin will not last nearly as long, which is why water is pushed through the RO membrane first. RO membranes, in combination with the prefilters, will remove between 90-96% of the impurities in the water, but are not effective at removing the remaining low concentrations, which is why DI is used after the RO.

Where do you have unlimited supply of DI water? That would be a nice resource!

And I agree that it's wise to buy water at $1 per 5 gallons if you use only a little per week (assuming thats once a week or so) and it's a good source. For me, I use probably 20-30 gallons a week (auto top-off and water changes), so at the price for water the RODI pays for itself within a year. I agree with Bill, though, pick up a TDS meter (~$20) to test the water youre purchasing. My tap water is about 250ppm TDS, and my purified RODI water is around 1 or 2ppm TDS.

Jahreefer · 03-20-2007, 08:49 AM

Spend the money, get the system. I still remember those day's of toting water and that sucked. I promise, their will be times you will need the water now but you dont have it cause it's at work. My unit removes 99% impurities through 5 stages of filtration. The filters in the RO side of things filter fine particulates down in order of size as it passes through the first 3 filters. The 4 step is the DI which ionizes the water and removes the fine particles that passed through the filter. The fifth step, can be left off, it a carbon scrub which clarifies the water and gives it a sparkle!
JUST WHAT CRVZ said!!!!!!

ScruffyRubicon · 03-20-2007, 08:53 AM

Quote:

Originally Posted by Jahreefer

Spend the money, get the system. I still remember those day's of toting water and that sucked. I promise, their will be times you will need the water now but you dont have it cause it's at work.

Agreed! I toted water until I just couldn't do it no more. Much more convenient to have it at home. Not to mention cheaper with the price of gas now.

Of course I had to install mine in the basement so I'm still carrying it up the stairs.

ckusnierek · 03-20-2007, 09:04 AM

Quote:

Originally Posted by crvz

Where do you have unlimited supply of DI water? That would be a nice resource!

Here at work we have a LARGE DI tank that is recharged every month!!!

I have found 4 stage DI/RO filters on ebay for 60(+35 shipping) Or should I fork the cash for a kent system 150-200$???

salt-rookie · 03-20-2007, 09:18 AM

FIRST....just because you pay 20 cents a gallon at the store doesn't make the water good. I used a local Culligan RODI machine in a grocery store....it was NOT properly maintained and I purchased a 5 gallon jug right after the RO membrane ruptured.....I lost EVERYTHING in my tank! IF you are going to buy water, buy sealed one gallon jugs of DISTILLED.

Secondly...RO/DI are COMPLEMENTARY processes. RO forces water molecules through a semi permiable membrane leaving MOST contaminants behind the membrane. The DI resin then uses valance to pull the remainder out.

Calculate how many gallons you will need to buy is a year....you'll find you'll save money buying your own...and you'll know its properly maintained!

zxcv123 · 03-20-2007, 09:25 AM

Quote:

Originally Posted by Jahreefer

Spend the money, get the system. I still remember those day's of toting water and that sucked. I promise, their will be times you will need the water now but you dont have it cause it's at work. My unit removes 99% impurities through 5 stages of filtration. The filters in the RO side of things filter fine particulates down in order of size as it passes through the first 3 filters. The 4 step is the DI which ionizes the water and removes the fine particles that passed through the filter. The fifth step, can be left off, it a carbon scrub which clarifies the water and gives it a sparkle!
JUST WHAT CRVZ said!!!!!!

abigtroutt · 03-20-2007, 09:37 AM

This is where I purchased mine http://www.abundantflowwater.com/htm...m_filters.html

I think an RO/DI is well worth the money.

salt-rookie · 03-20-2007, 09:42 AM

IMO...Water General on eBay! Great product GREAT service, Can'T BEAT the price!

GordoB · 03-20-2007, 09:54 AM

When you guys do water changes, how does it work? Let's say you have a 75 GPD unit.....do you have to set up a container to collect fresh water all day, or does the water store well, so you can collect it over time? (I'm trying to figure out if a 75 GPD unit would be sufficient for a 135 gal tank.)

Thanks,
Brad

salt-rookie · 03-20-2007, 10:06 AM

I run a 1/4" tube from my RODI through a Kent Float Valve into my salt water reservoir. As soon as I pump the salt water out for a water change, it automatically refills the bucket...I then put 4 tablespoon of epsom salt, 2 teaspoons of Turbo Calcium and 15.5 cups of IO in and I'm ready for the next Sunday! EASY!

Jahreefer · 03-20-2007, 10:15 AM

I have a 40 gal reservoir I made out of a rubbermaid container and float valve which runs to my RO/DI system. I always make my new water 2-3 days before I do a water change. THis way the day I take out old water, the new water is right there, parameters are good, and its ready to go. Just my .02. Oh yeah I have a American General 100 GPD RO/DI unit 5 stage, never had a problem. I change filters only once a year, recharge DI every 6 months. TDS on my system water this morning was 1 ppm...that is good as it gets...Standard tap water, is 400 ppm.
Also suggest investing in a TDS/PH meter by Hanna.

GordoB · 03-20-2007, 10:36 AM

Not to hyjack the thread, but how do you figure out how many gallons per day you need for the tank size?

Brad

salt-rookie · 03-20-2007, 10:39 AM

I'd estimate 2-3 gallons evaporation goes through the auto topoff. I have 1 180 show with a fuge and sump...255 gallon total water volume.