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sonubhai

sonubhai

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Hello All:
So after 3 years of faithful service my Kenmore RO unit died (or maybe I killed it). I need to buy a new RODI unit without spending an arm and a leg for it. I am leaning towards BRS 150gpd water saver unit 229 or the spectra pure 90gpd 2:1 rodi unit 269. What do you all use and can recommend. Is zero TDS over rated. My last unit gave me between 5 and 12 TDS,
 
Nutramar Foods
Don't fall for the water saver claims, it's not that easy.
Before attempting to reduce your waste ratio you must know your tap waters calcium carbonate hardness and TDS at a minimum. You also need to know your incoming pressure as it takes at least 65 psi to operate any dual membrane system. If you have hard water and higher than normal TDS then don't even think about reducing the waste as it will cause the membrane to fail prematurely and DI replacements will become more frequent so overall cost of ownership skyrockets.
I am a big fan of Spectrapure. No other vendor specially treats all their RO membranes which is proven to increase their efficiency then either batch tests or individually hand tests them for quality control. This one simple thing can double your DI life and lower cost of ownership. Add to that they are the only vendor to custom blend every ounce of their DI resins in house so you get only the best, freshest resin intended for reef use. I have been told they reject more resin shipments due to quality control issues than most vendors combined sell and I believe it. When I was using resin from other well known vendors I would get 150 gallons per cartridge, today that is over 1000 gallons on the MaxCap cartridge and 3000 gallons on the SilicaBuster cartridge. Huge cost savings.

I know the Spectrapure 2:1 systems used to come with a hardness test kit and two flow restrictors so you could first test your water quality then use the correct flow restrictor for your exact conditions. Its not going to be 2:1 or even 3:1 for everyone since their water is not all the same. I would take extended filter, membrane and DI life over a little water savings any day. The water gets recycled and used over and over again so it is not really wasted.
 
Chewy.com
You can pick up a calcium carbonate hardness test kit anywhere that sells water softeners like Sears, Home Depot or Lowes. A hose bib pressure gauge is around $8-$10 at any of those places also.
To operate a RO/DI you need at least 40 psi absolute minimum and 60-80 is better. To operate a RO/DI with dual RO membranes it takes a minimum of 65 psi again 80 or more is better.
The reason for this is you are taking the waste from the first membrane and sending it through the second membrane so it takes additional pressure. This is also why reducing the waste ratio on a dual membrane system does not work, it soon fouls or plugs the membranes as you are sending concentrated TDS to the second membrane, even more reason why it is important to keep the waste at 4:1 or so if you expect the membranes to last. If it were really that easy all the vendors who have been doing RO for 30+ years would have been reducing waste years ago, they are not stupid. Membranes must stay flushed in order to operate and last, that is something there is no getting around. Reduce the waste and the cost of ownership goes up due to more frequent replacements. If you have very soft water you can reduce it some but not like some vendors claim.
 
Nutramar Foods
Its almost impossible to beat this:
http://spectrapure.com/RO-RODI/RODI...ement-Filter Kit-TDS Meters-Chlorine-Test-Kit

For $160 you get a 90 GPD reef quality RO/DI with an inline pressure gauge, handheld TDS meter, low range chlorine test kit to monitor the carbon block condition plus your first set of replacement filters and DI cartridge. They use capilllary tube flow restrictors so you can trim the length of the restrictor to adjust the waste ratio to fit your exact water conditions. If you do have soft water and low TDS you can install a restrictor closer to 2:1, if its moderately hard you can adjust it to 3:1 and if it is hard and high TDS stick with the recommended 4:1. Takes just a few minutes to check and adjust the ratio once you are set up and running. I often suggest having two capillary tube restrictors, one trimmed for colder winter water and one for warmer summer water temps since the temperature of the water will change the waste ratio. As water warms up it becomes more viscous or fluid so passes through the RO membrane easier and waste goes down, as it gets colder it is more dense so does not pass through the membrane as easily so waste goes up. If you take a minute or so and swap the restrictor you can keep the waste ratio more constant even though the water temperature changes. All it takes is an extra $6 capillary tube and a sharp razor blade to trim the overall length.

Or if you really need the extra capacity and have at least 65 psi you could go with something like this:
http://spectrapure.com/RO-RODI/RODI-SYSTEMS/MaxPureMPDI-180-GPD-RODI-System-OPEN-BOX

I used to have a dual membrane system but found I really didn't need to produce water that fast since I can store about 50 gallons at all times.
 
www.dinkinsaquaticgardens.com
I keep RO/DI for 6 months or more with no issues. I use a 23 gallon Rubbermaid recycling can for my ATO storage, a Rubbermaid Roughneck 30 gallon on wheels for water changes and five or six 5G drinking water jugs for extra storage. I don't mix my new saltwater until the day I am ready for it, usually an hour or so ahead is all unless the temperature needs correcting and I use an old Mag 9.5 pump to raise the temp and aerate the water since it runs so hot.
Most Rubbermaid trashcans, especially the Brutes are food safe. Many are still food safe they just were not subjected to the years of testing and thounsands of dollars it costs to get the NSF rating since they are not primarily intended for food preparation or storage. Much of the plastic materials come out of the same batches but why spend the time and money if its intended purpose is trash collection or to store the kids toys?
 
I have had an Air, Water, & Ice Reefkeeper RODI for years with no issues. 0 tds water for about a year before cartridges need replacing. Has been a very reliable system for me and is only $150 for 75 gpd. Bonus is you get 10% off with your club code (look on their sponsor forum on here). I am not affiliated with them, just a very happy customer.
 
Tidal Gardens
+1 on the spectrapure. Best IMO, that deal AZ posted you will not beat period. They also have a discount code until May 31 to get an extra 10% off your entire order. Just use spring10 your getting 90gpd unit and a set of extra filters and tds meter.
 
Nutramar Foods
AZDesertRat said:
You can pick up a calcium carbonate hardness test kit anywhere that sells water softeners like Sears, Home Depot or Lowes. A hose bib pressure gauge is around $8-$10 at any of those places also.
To operate a RO/DI you need at least 40 psi absolute minimum and 60-80 is better. To operate a RO/DI with dual RO membranes it takes a minimum of 65 psi again 80 or more is better.
The reason for this is you are taking the waste from the first membrane and sending it through the second membrane so it takes additional pressure. This is also why reducing the waste ratio on a dual membrane system does not work, it soon fouls or plugs the membranes as you are sending concentrated TDS to the second membrane, even more reason why it is important to keep the waste at 4:1 or so if you expect the membranes to last. If it were really that easy all the vendors who have been doing RO for 30+ years would have been reducing waste years ago, they are not stupid. Membranes must stay flushed in order to operate and last, that is something there is no getting around. Reduce the waste and the cost of ownership goes up due to more frequent replacements. If you have very soft water you can reduce it some but not like some vendors claim.
Click to expand...
I just setup a rodi, it's a 6 stage the final stage after the di is a coconut shell filter for sweeter tasting water.I've seen conflicting opinions on using rodi for drinking water.
Is this stage necessary for reef tank water?
Should I connect this stage after RO for drinking?
 
Top Shelf Aquatics
AI Hydra

IF YOU HAD TO TAKE A REEFING EXAM, WOULD YOU PASS?

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  • Not yet, but I have one that I want to buy in mind!

    Votes: 9 12.9%

  • No.

    Votes: 26 37.1%

  • Other (please explain).

    Votes: 3 4.3%
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