Looking for new RO/DI unit

Hello everyone, got a question regarding ro/di units. Since moving into my home 5 years ago i am finally getting ready to set up my reef tank again. I had the luxury before of getting my ro/di water from a friend of mine that moved away a year ago. So I am on the market to buy one for myself. I was looking at dr foster and found one that I feel will work well for a good price.
Aquarium Water Quality: Pure-Flo II RO Units
above is the link I was looking at the 3 stage with pump as I have some horrid water pressure problems (50y/o home).
I was looking to add the DI unit shown here to the system.
Aquarium Water Quality: Pure-Flo II Add-On Deionization Canister

So i guess my question is: Does this look like a good system or is there a better one that may also be cheaper?

Thanks
Bob

Hi Bob and :welcome: to TR!

I am not the most knowledgeable person on RO/DI systems but here are a couple of tips. You will probably want a 100 GDP unit. That sounds like a lot but that is only how much the unit produces under optimum conditions. You definitely want a DI cartridge.

Here are a couple of podcasts that should help you.
http://www.talkingreef.com/forums/po...ode-105-a.html
http://www.talkingreef.com/forums/po...ode-106-a.html

here is some really good info from Russ at Buckeye Field Supply (an outstanding RO/DI company)

his post is near the bottom of the page under "buckeyefieldsupply"

http://www.talkingreef.com/forums/podcast-episodes/5299-ro-di-video-part-2-podcast-episode-106-a.html#post122585

Like Carmie post I would go with 100gpd. Cause if you need to make allot of water bigger is better.
Now I would go with a 4stage + DI = 5 stage filter. Now you can get some good deals on ebay 5stage RO/DI around $100-150 and get the booster pump for around $50-60.

Here is a 5 stage + UV
http://cgi.ebay.com/6-Stage-RO-DI-UV...item5ad5f50d68
I don't see why you would need a UV on a RO/DI. But you could build your own setup with pump that is better for less.

Thanks everyone for the replies, was going for a 100 gpd system, thanks for the link carmie and activating me!

Reef keeper Bobby thanks for the link as well, am going to look over his website and after reading everything from the link buy a tds meter before I make my selection, I know my tap water quality is going to be bad.

Any more suggestions are welcome so keep them coming
Bob

Hi Bob Welcome to TR.

i would suggest a 75gpd unit, because of the rejection rate (explained in the link above).

For an RO that feeds a DI stage, use of a higher rejection membrane (for example, a 75 gpd @ 98% vs. a 100 gpd @ 90%) makes sense. If you want high rejection, faster production, and have at least 60-65 psi line pressure, think about a 150 gpd membrane. Or just use a 75 gpd membrane and add some non pressurized storage capacity to your system (e.g., an 5 gallon bucket or Brute trash can).

Russ

Welcome to TR, Bob. A hand held TDS meter is a great tool. Consider getting an in line TDS meter with your unit. It can check two TDS points with the push of a button. Very convenient. Most people check their incoming raw water (my well water is 589 ppm TDS) and their final output water. I hooked mine to read the RO output (50 TDS) and the the DI cartridge output (0 TDS). I rarely find it necessary to read my well water since I know it is atrocious. That’s not going to change. It’s the output of the unit I’m most interested in.

Russ, PM sent. Thanks for the help.

Dick

Thank you everyone for the suggestions again.

Russ, what of your products available would you suggest, as you are far more qualified than myself. I am sure than without even testing my municipal water supply I know that there is a good bit of chlorine as well as I have some horrible hard water coming into my home. I am not concerned as much with how much output I have as much as I would like the least waste. Also my water pressure tends to run low so I am wondering if i should also purchase a pump to increase the effectiveness?
I have 3 weeks till vacation then get some remodeling done so I can set up my tank. cant wait !

Bob

We just introduced our new Triton RODI Series - which have about a 1:1 waste to purified water ratio. If you'll PM me your email address I can send you a pdf.

Russ

Hey Russ,

Thanks for the pdf sent. I’d like to see the Triton series, too.

Dick

Russ brings up a good point on the rejection rate of 75 vs 100 GPD membranes, with Dow Filmtec the difference is 96-98% rejection for the 75 GPD and smaller versus only 90% rejection for their 100 GPD membrane.
What Dow does not tell you is the 100 GPD is not even approved for drinking water in many countries, the US included, and is actually rated "For Pool and Spa Use" by the ANSI/NSF.

You need to watch what you buy closely, many ebay type vendors will happily sell you this 100 GPD NanoFilter membrane as a true RO and its not the same. The significance of this is a rough rule of thumb shows for every 2% you increase the membranes efficiency you DOUBLE the life of your DI resin. A 6 to 8% increase in membrane efficiency can save you a ton of money in a very short time in DI replacements alone, imagine if you own the unit for 3-5 years!

This is not the case with all 100GPD membranes though so things get a bit confusing. GE Water (Osmonics, Desal) states their 100 GPD membrane is 96-98% rejection and its true. The dilema is, its not really a 100GPD membrane when compared to Dow Filmtecs membranes and here is why.

Dow Filmtec tests and rates their membranes at 50 psi water pressure, 77 degrees F water temperature and with 250 ppm TDS softened water. On the other hand GE tests and rates their at 65 psi, 77 degrees and 500 ppm TDS. Notice the 15 psi difference?

Most households don't have 65 psi available at the tap much less after a prefilter and carbon block in front of a RO membrane so the Dow figure of 50 psi is more realistic. If you take the graphs supplied by both manufacturers and lay them on top of each other you will find them to be almost identical, 75 GPD at 50 psi, 90 GPD at 60 psi, 100 GPD at 65 psi etc. So as I said earlier, the 100 GPD GE is the same as the 75 GPD Dow Filmtec for all intents and purposes.

As long as you stick with a knowledgable vendor such as Russ, who by the way will try and talk you out of the 100 GPD if you ask for it, you should get a good system. Not all RO/DI units are the same even though they may visibly appear similar, its what is inside that counts the most.

As for inline vs handheld TDS meters, I have multiples of both and much prefer the handhelds, especially the HM Digital COM-100. The inlines have limitations, the worts of which is it is a dedicated meter and can only measure two permanent points, usually after the RO membrane and after the DI filter. They cannot be dunked in a glass of water or in your storage reservoir since thye depend on flow past the probe to work. Another is they are not temperature compensated so can be significantly off. They measure air temperature on the exterior of the probe, not water temperature so if they are different the readings will be off. How often are your water and air temperatures exactly the same? I use two of them as rough guides only.

I use the handhelds when I want accuracy and love their portability. I can check the tap water, ATO reservoir, bottled water, my neighbors tap, the LFS, the Water vending machine etc all with the touch of a button. Just make sure you keep it clean and capped when not in use and it will last for years.

hey whats this, holding out on the good stuff rusty, feel free to fire away with the new info also:up:.

Ive always been happy with my NSW & top-off water buying in bulk, however ive started to notice since shelving my bigger cars over the last 6 months, that logistically, its getting a sh^t load harder & more of an effort than its worth.

A new unit might be the most viable way to go. What would you need from me to determine any issues operating your units in a different country?

Quote:

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Originally Posted by Amphibious

Hey Russ,

Thanks for the pdf sent. I’d like to see the Triton series, too.

Dick

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Sorry -can you send your email address again? Deleted it already.

Russ

Quote:

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Originally Posted by V

hey whats this, holding out on the good stuff rusty, feel free to fire away with the new info also:up:.

Ive always been happy with my NSW & top-off water buying in bulk, however ive started to notice since shelving my bigger cars over the last 6 months, that logistically, its getting a sh^t load harder & more of an effort than its worth.

A new unit might be the most viable way to go. What would you need from me to determine any issues operating your units in a different country?

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We've sent a number of units down under already. Your electric wall sockets are 240V. right? If yes, you'd need a converter to bring that down to 110/120, which will run the pump. Other than that, there shouldn't be any issues.

What's your email?

Russ

Wow am I glad that I found TR, there are so many knowledgeable people on here and everyone is willing to help. Thanks again Russ it is great to have you as a resource, I do have a question though. Should I worry about the hard water that I have as well as the chlorine that my water treatment plant use to process the water. Or do you feel the the Triton unit will handle this with no problem, just wondering if i needed any additional prefilters?

Thanks for you patience,
Bob

yeah, 240v. step down only, definatly dont have to worry bout the variations in pressure?.
Yup, send me the details, along with prices to bud, i want to know what the damage will be.

My email is veriann@inorbit.com
Ampage, is dick@theculturedreef.com last i checked.

see, thats what im talking about, no BS responces, potentually gives you a sale half a world away. I beter not say that to loud though, cause ive bought diddly squat off my mate Ampage as of yet - and hes a buddy:huh:

Whats the average wattage?, the step down transformers here are somewhere from 50w -$50 ...through to 1000w - $380

This is turning out to be a really educational thread. Thanks!

yeah i'll second that. This and the other one we had a blip on after all that time

V any word back on the prices for these units? Russ has not been on in a few days and just seeing if you may have got a price list cant find these on the website.

Quote:

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Originally Posted by Rostr02

Wow am I glad that I found TR, there are so many knowledgeable people on here and everyone is willing to help. Thanks again Russ it is great to have you as a resource, I do have a question though. Should I worry about the hard water that I have as well as the chlorine that my water treatment plant use to process the water. Or do you feel the the Triton unit will handle this with no problem, just wondering if i needed any additional prefilters?

Thanks for you patience,
Bob

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Well... Hard water is always a problem for RO membranes. The harder the water the more likely you are to have problems with scale in the membrane. Ideally, you'd send softened water to the Triton or any other RO system, but most people don't.

The Triton, as well as all our other systems are designed to remove chlorine. They all have high qulaity carbon blocks.

Russ

Quote:

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Originally Posted by Rostr02

V any word back on the prices for these units? Russ has not been on in a few days and just seeing if you may have got a price list cant find these on the website.

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Sorry ...prices should be available soon. Its always a struggle finding the right balance between high quality parts/higher prices and economy parts.

We trend towards the higher quality parts even if they drive the cost up a bit.

Russ

Thanks Russ. I have plans to put a full house water softener system in about 6months or so when I re do my plumbing. Part of the problem is my house is 50 plus years old and they decided to use iron pipes to carry most of the water. . . . . . Those need replaced. But like all things in setting up marine tanks, you are rewarded for you patience,

Thanks again

Bob