Questions about RO/DI

Axolotl · 01/25/2012, 11:30 PM

Hello I'm currently looking for a used RO/DI unit on craigslist here locally. I have seen several listed at various pricing but dont really know exactly what I need. What questions i should ask them, and basically what to look for in the unit. They range from $45-$250 in price.

WindowMaker · 01/25/2012, 11:36 PM

I would say ask how old the cartridges are, but you should probably replace them all anyways. Just make sure it doesnt leak...

divewsharks · 01/26/2012, 01:55 AM

^+1.
Water test it, and replace all the cartridges.
For $200 (or less) you can get brand new from 'the filter guys'. 5 stage system 75gpd. You can add a 2nd membrane and boost performance significantly.

webfinger · 01/26/2012, 02:16 AM

You need to know what the output volume is, how many stages. Find out if it has a TDS meter (wouldn't live without one now). Also find out the age. I had a Maxxum unit that I bought and one of the housings cracked and couldn't get another the same size.

PRDubois · 01/26/2012, 02:33 AM

Quote:

Originally Posted by divewsharks

^+1.
Water test it, and replace all the cartridges.
For $200 (or less) you can get brand new from 'the filter guys'. 5 stage system 75gpd. You can add a 2nd membrane and boost performance significantly.

Buy new! by the time you buy all new cartridges for the used one you could have a new one with great support.

fishgate · 01/26/2012, 06:35 AM

Quote:

Originally Posted by PRDubois

Buy new! by the time you buy all new cartridges for the used one you could have a new one with great support.

+100 I got my new Coralife 4 stage 50gpd for $150 shipped from a reputable seller. It's foolish to buy something like this from Craigslist. The membrane alone is over $100.

divewsharks · 01/26/2012, 09:09 PM

Quote:

Originally Posted by fishgate

+100 I got my new Coralife 4 stage 50gpd for $150 shipped from a reputable seller. It's foolish to buy something like this from Craigslist. The membrane alone is over $100.

A membrane should not cost you $100; either way, i'd go with brand new as you won't save any money buying used.

rogster · 01/27/2012, 08:51 AM

Quote:

Originally Posted by Axolotl

Hello I'm currently looking for a used RO/DI unit on craigslist here locally. I have seen several listed at various pricing but dont really know exactly what I need. What questions i should ask them, and basically what to look for in the unit. They range from $45-$250 in price.

No worth it. Too much media replacement , hose, connector needed.

Buy new

01/25/2012, 11:30 PM	#1
Axolotl Registered Member Join Date: Dec 2011 Location: Kansas City, Missouri Posts: 142	Questions about RO/DI Hello I'm currently looking for a used RO/DI unit on craigslist here locally. I have seen several listed at various pricing but dont really know exactly what I need. What questions i should ask them, and basically what to look for in the unit. They range from $45-$250 in price.

01/25/2012, 11:36 PM	#2
WindowMaker Moved On Join Date: Nov 2011 Posts: 216	I would say ask how old the cartridges are, but you should probably replace them all anyways. Just make sure it doesnt leak...

01/26/2012, 01:55 AM	#3
divewsharks Registered Member Join Date: Apr 2004 Location: San Jose, CA Posts: 1,905	^+1. Water test it, and replace all the cartridges. For $200 (or less) you can get brand new from 'the filter guys'. 5 stage system 75gpd. You can add a 2nd membrane and boost performance significantly.

01/26/2012, 02:16 AM	#4
webfinger Registered Member Join Date: Dec 2010 Location: Portland, Oregon USA Posts: 55	You need to know what the output volume is, how many stages. Find out if it has a TDS meter (wouldn't live without one now). Also find out the age. I had a Maxxum unit that I bought and one of the housings cracked and couldn't get another the same size.