RO/DI Unit Opinion

theguru · Aug 20, 2012

Stealth sales reps are a reality in the world. Heck there was even a movie about stealth marketing. I am up front telling everyone who and what I am. I want to help, I have the credentials and the expertise.
I should be able to respond to your questions with real answers.
One answer I put forward today is that the bond between the Chlorine and the Ammonia is not broken by coconut carbon.
If Chlorine or Ammonia reach the membrane surface the surface will be degraded.

Thanks everyone for welcoming me to R & R

AZDesertRat · Aug 20, 2012

I have posted my qualifications many many times in all the forums. Basically it is 37+ years as a certified water/wastewater treatment professional including 6.5 years doing start ups, training and writing manuals for municipal membrane treatment systems. I am not affiliated with any filter manufacturer or vendor in any way and have personally owned 7 or 8 RO and RO/DI systems over the last 15-20 years including a Typhoon III.

There are many articles on chloramines and their removal including these:
Chloramine and the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com
Chloramines - Reef Central Online Community

With todays modern extruded carbon blocks the technology has greatly improved. They are able to blend different carbons and different pore sizes along with catalytic components, zeolites and oxidizing medias in one extruded block so they perform many fuctions. Years ago when carbon blocks were molded rather than extruded that was not the case and why you saw things like multiple carbons and granular catalytic carbon medias.

theguru · Aug 20, 2012

I suspect that only reef keepers leaving the hobby or expanding, would have a reason to sell a used RODI.
Problems ? What problems the only moving part in the entire system is the (ASOV) automatic shut off valve.
Last I checked (ASOV) automatic shut off valves aren't expensive at all, they take what two minutes to replace?

AZDesertRat · Aug 20, 2012

As you know, many vendors such as the ebay variety still use non ANSI/NSF or UPC components which are not the same quality as tested or rated components are. I have seen more than my share or sump, lid and fitting failures as I am sure you have also. Look at how many still use old compression fittings and even small horizontal tubes and call them DI filters.
If you can find a decent system for a decent pricer jump on it but I find by the time you replace the filters and misc components to get it working you have more invested than with a new guaranteed system from a trusted vendor. Thats been my personal experience anyway.

theguru · Aug 21, 2012

No argument about quality, I am commenting on Hype!

AZDesertRat said:
As you know, many vendors such as the ebay variety still use non ANSI/NSF or UPC components which are not the same quality as tested or rated components are. I have seen more than my share or sump, lid and fitting failures as I am sure you have also. Look at how many still use old compression fittings and even small horizontal tubes and call them DI filters.
If you can find a decent system for a decent pricer jump on it but I find by the time you replace the filters and misc components to get it working you have more invested than with a new guaranteed system from a trusted vendor. Thats been my personal experience anyway.

Quality Yes Hype no !
Hype like one micron absolute vs. one micron nominal drive me nuts. Filmtec the preeminent membrane manufacturer,requires a slit density index of less than (3) three.
Water filtered down to (5) microns is defined as Sparkling water. It would be hard to imagine getting a silt density measurement from SPARKLING water.
:neutral:

AZDesertRat · Aug 21, 2012

You are entitled to your opinion and I welcome it. Always nice to have more knowledgable people here on the forums.

I personally find both carbon blocks and RO membranes work better and last longer with better prefiltration. When thye both work better and last longer so does the DI resin so the overall cost of operation is less to the end user.

dhutcheson · Aug 21, 2012

A RODI system is one of the few items in reef keeping that actually pays for itsself over a pretty short time vs buying water. IMO the filters are what matter in the system. While I think the canisters do have varying degrees of quality they basically do the same thing. Also be sure to get a TDS meter it tells you how clean your water is going in and coming out and lets you know when its time to replace filters.

Fatman · Aug 21, 2012

+1 on the SpectraPure. Have one and it's been great.

theguru · Aug 22, 2012

Canister failure product quality or improper usage?

dhutcheson said:
A RODI system is one of the few items in reef keeping that actually pays for itsself over a pretty short time vs buying water. IMO the filters are what matter in the system. While I think the canisters do have varying degrees of quality they basically do the same thing. Also be sure to get a TDS meter it tells you how clean your water is going in and coming out and lets you know when its time to replace filters.

YES !!!! Get an excellent high rejection membrane protected by excellent quality pre-filters. Keep the water recovery ratio low and the pressure as high as you can, in other words change pre-filters often.
Consider an in- line dual reading tds meter, measure the membrane output then the DI. The DI is totally dependent on the membrane.
In my thirty plus years of using reverse osmosis to treat all sorts of water problems, using very large industrial duty machines with membrane assemblies costing tens of thousands of dollars, I never considered a one micron pre-filter assembly.
We built all of our equipment over spec by at least (30%) pumps everything, our systems sold them selves and we never had a warranty claim filed with Filmtec.
A membrane pore is measured in Angstroms not microns. The specification for Filmtec membranes an SDI (silt density index) of less than three, that is only the manufacturer speaking DOW Chemical.
Use a one micron filter no problem (overkill) paying extra for an absolute, or basing your decision to purchase on the fact that the unit has an absolute sediment filter vs a nominal one micron is IMO buying into hype. Thanks for the read, hope it helped you!

theguru · Aug 25, 2012

Good morning everyone, finally no rain in my area. Tuesday ought to change that Hurricane Issac . Remember to make up extra water and prepare for power outages all along the West coast of Florida.
Water for you and the tank, don't forget you will still need to top off!