Over doing the RO/DI

[Basile]

Well i think i found my guy; http://www.reefsupplies.ca/online-st...ectrapure.html because we have excellent pressure here in the capital, good water no contaminants, i'll verify with city official whats the water purifying methods and that it. thansks for your input.

[Cal_stir]

Originally Posted by Basile

Well i think i found my guy; http://www.reefsupplies.ca/online-st...ectrapure.html because we have excellent pressure here in the capital, good water no contaminants, i'll verify with city official whats the water purifying methods and that it. thansks for your input.

Knowing our government you probably have bottled water coming out of your tap, lol.

[Basile]

Originally Posted by Cal_stir

Knowing our government you probably have bottled water coming out of your tap, lol.

LOL Knowing yours i hate to see where it comes from LOL...

[Cal_stir]

I think mine comes from the toilet.

[Basile]

Originally Posted by Cal_stir

I think mine comes from the toilet.

LOL peace bro

[mike31154]

A water report from your provider is definitely a great place to start prior to deciding how many stages you may need. Should be available online, it's pretty much mandatory for them to make monthly & annual reports publicly accessible. These should not only show TDS, but also 'what' those dissolved solids are, i.e. broken down into the elements & minerals in your water. You'd be surprised at some of the stuff still coming down the line. There are fairly strict guidelines these days but it largely depends on the source as to what your TDS will consist of. The report should provide a comparison between what you get out of the tap vs what's considered safe with regard to potentially harmful elements in potable water.

Verifying the water pressure with a gauge is also not a bad idea. Anything over 60 psi is a good number, lower may indicate the requirement for a booster pump. Before spending the $$s on a booster pump, check your house for a pressure regulating (reducing?) valve (PRV). Most jurisdictions these days require them by code to protect your plumbing from surges. I've tweaked the PRV in my house to provide close to 110 psi from the standard 60-70. Why pay for a booster pump when the city already provides a higher pressure & you're paying for that through your water bill? You need to ensure your plumbing is in good shape though & there will be a higher risk of a leak. I think most plumbing is rated to well over 200 psi, but I'm not a plumber, so don't take my word on that!

While the focus here has been on the number of stages, how you run your RO/DI can have a significant impact on filter life and the quality of product water. Adding more filters is not always the answer, since each stage you add before the RO membrane will cut down the water pressure to it & slow down the output. Quality of filters can vary, so watch what you buy there, especially when it comes to carbon blocks. On most days, my source TDS is around 180 and my 75 gpd membrane, which is still the original from April 2009, will produce RO water TDS of 1 within 5-10 minutes after I fire the system up. During the winter, with colder water coming in, it will actually produce 0 TDS water. Speaking of membranes, a 75 gpd may be preferable over a 90 gpd since it's ability to lower TDS is better. This is worth considering especially in our application, where a DI stage follows the membrane. The lower you can get the TDS before it reaches the DI stage, the longer the media will last. Down side is that it takes a tad longer to produce water. But when you think about it, the difference between 90 & 70 is not all that much in the big picture, when you're looking to save $$s on DI media. The two costliest components to replace on your system are the RO membrane & DI media, so the more you can do to make those last, the more you save.

I currently run 5 stages. My system came with two carbon stages which I found to be overkill since my water is treated with chlorine, not chloramine. Generally if your source water is chloramine treated, 2 carbon stages are required to protect the membrane. I replaced the extra carbon stage with a 1 micron sediment filter. So now I have a 5 micron sediment, 1 micron sediment, 0.5 micron carbon block, 75 gpd RO membrane & DI stage.

My DI media went from April 2009 to June 2012 before TDS finally went from 0 to 1. I keep track of water through my system on an Excel spreadsheet & figure I put about 15000 gallons through in that time. The calculation includes pure water produced, plus an estimate of waste water based on a 1:4 pure vs waste ratio to give me total gallons throughput. Since the carbon block was rated for 20,000 gallons, I decided to change it at the same time, even though a chlorine test with a swimming pool test strip showed no traces of chlorine after the carbon stage. I figured at 15000 gallons, the carbon stage owed me nothing.

Some info on what I think has helped maximize life of filters/DI media based on own experience follows:

1. I manually flush the RO membrane for about a minute before & after each production cycle. The first 1/2 gallon of RO water produced goes into a waste bucket, since it takes a good 2-3 minutes for the TDS to get down to 2 then 1. It also allows the TDS after the sediment filters to stabilize. Not long ago, I added a second dual TDS meter allowing me to compare source TDS to TDS after the sediment filters. I found that on start up, TDS after the sediment filters is actually higher than the source TDS. I attribute this to junk dissolving back into solution in the cartridge housings while the system sits idle. Once fired back up it takes a few minutes for TDS after sediment filters to drop a couple of points below source TDS. During this time, the RO membrane is dealing with higher TDS and if it's feeding the DI stage, it will be working harder. Lesson here is to produce a few gallons of RO for use around the house before opening the valve to the DI stage;

2. I generally produce a minimum of 6 gallons per session. Most of the time I make more, starting with 6 gallons of RO, then 7 to 25 gallons of DI. I never feed the DI stage until I've produced 6 gallons of RO water. This ensures the TDS out of the membrane is as low as possible, usually 1 or 0 before the DI needs to go to work. Short production cycles will definitely be harder on your filters and you'll get pretty crappy production water for the first few minutes for the reasons highlighted in 1. above. A heads up for those folks who have their system plumbed directly to their ATO & allow it to be controlled by automatic shutoff switch.

Other things worth noting after running the system over the years is that I don't trust the auto shutoff valve (ASO). I'm actually considering removing the thing as it will simplify the plumbing & probably make the RO membrane more efficient with one less restricting component. I tried using the float valve in my NSW make up container when the system was new but the waste water would always continue to run after the float valve closed. Played around with the ASO & considered getting a new one, but gave up on that idea since I'm just too nervous about the reliability of the device. I have no drain in my basement floor, so chance of a flood due to an iffy little device is enough for me to be content without the automation. I'm always at home when I produce water & use the timer on my oven as a reminder to check on things periodically. I've also installed a water detector on the floor & it's saved my bacon a couple of times.

It's useful to have clear housings for your sediment filters as they provide a visual indication of their condition. I've read that a vertical DI stage is better than a horizontal one, but can't verify that from personal experience. My DI stage is vertical & has a clear housing. The initial batch of DI media was colour changing so I guess a clear housing is useful there, although the DI media I have in there now is not colour changing. I'll rely on my TDS meter to tell me when it's exhausted. Carbon block also has a clear housing, but that's probably not required - I can't think of any useful visual indicator for this stage. Difference in price between the white & clear housings is not a deal breaker, so if in doubt, clear is good I suppose. I think the white ones may be more robust.

So yeah, get a water report, check your water pressure & order away based on that!

[Basile]

Originally Posted by mike31154

A water report from your provider is definitely a great place to start prior to deciding how many stages you may need. Should be available online, it's pretty much mandatory for them to make monthly & annual reports publicly accessible. These should not only show TDS, but also 'what' those dissolved solids are, i.e. broken down into the elements & minerals in your water. You'd be surprised at some of the stuff still coming down the line. There are fairly strict guidelines these days but it largely depends on the source as to what your TDS will consist of. The report should provide a comparison between what you get out of the tap vs what's considered safe with regard to potentially harmful elements in potable water.

Verifying the water pressure with a gauge is also not a bad idea. Anything over 60 psi is a good number, lower may indicate the requirement for a booster pump. Before spending the $$s on a booster pump, check your house for a pressure regulating (reducing?) valve (PRV). Most jurisdictions these days require them by code to protect your plumbing from surges. I've tweaked the PRV in my house to provide close to 110 psi from the standard 60-70. Why pay for a booster pump when the city already provides a higher pressure & you're paying for that through your water bill? You need to ensure your plumbing is in good shape though & there will be a higher risk of a leak. I think most plumbing is rated to well over 200 psi, but I'm not a plumber, so don't take my word on that!

While the focus here has been on the number of stages, how you run your RO/DI can have a significant impact on filter life and the quality of product water. Adding more filters is not always the answer, since each stage you add before the RO membrane will cut down the water pressure to it & slow down the output. Quality of filters can vary, so watch what you buy there, especially when it comes to carbon blocks. On most days, my source TDS is around 180 and my 75 gpd membrane, which is still the original from April 2009, will produce RO water TDS of 1 within 5-10 minutes after I fire the system up. During the winter, with colder water coming in, it will actually produce 0 TDS water. Speaking of membranes, a 75 gpd may be preferable over a 90 gpd since it's ability to lower TDS is better. This is worth considering especially in our application, where a DI stage follows the membrane. The lower you can get the TDS before it reaches the DI stage, the longer the media will last. Down side is that it takes a tad longer to produce water. But when you think about it, the difference between 90 & 70 is not all that much in the big picture, when you're looking to save $$s on DI media. The two costliest components to replace on your system are the RO membrane & DI media, so the more you can do to make those last, the more you save.

I currently run 5 stages. My system came with two carbon stages which I found to be overkill since my water is treated with chlorine, not chloramine. Generally if your source water is chloramine treated, 2 carbon stages are required to protect the membrane. I replaced the extra carbon stage with a 1 micron sediment filter. So now I have a 5 micron sediment, 1 micron sediment, 0.5 micron carbon block, 75 gpd membrane & DI stage.

My DI media went from April 2009 to June 2012 before TDS finally went from 0 to 1. I keep track of water through my system on an Excel spreadsheet & figure I put about 15000 gallons through in that time. The calculation includes pure water produced, plus an estimate of waste water based on a 1:4 pure vs waste ratio to give me total gallons throughput. Since the carbon block was rated for 20,000 gallons, I decided to change it at the same time, even though a chlorine test with a swimming pool test strip showed no traces of chlorine after the carbon stage. I figured at 15000 gallons, the carbon stage owed me nothing.

Some info on what I think has helped maximize life of filters/DI media based on own experience follows:

1. I manually flush the membrane for about a minute before & after each production cycle. The first 1/2 gallon of RO water produced goes into a waste bucket, since it takes a good 2-3 minutes for the TDS to get down to 2 then 1. It also allows the TDS after the sediment filters to stabilize. Not long ago, I added a second dual TDS meter allowing me to compare source TDS to TDS after the sediment filters. I found that on start up, TDS after the sediment filters is actually higher than the source TDS. I attribute this to junk dissolving back into solution in the cartridge housings while the system sits idle. Once fired back up it takes a few minutes for TDS after sediment filters to drop a couple of points below source TDS. During this time, your RO membrane is dealing with higher TDS and if you're feeding the DI stage, it will be working harder. Lesson here is to produce a few gallons of RO for use around the house before opening the valve to the DI stage;

2. I generally produce a minimum of 6 gallons per session. Most of the time I make more, starting with 6 gallons of RO, then 7 to 25 gallons of DI. I never feed the DI stage until I've produced 6 gallons of RO water. This ensures the TDS out of the membrane is as low as possible, usually 1 or 0 before the DI needs to go to work. Short production cycles will definitely be harder on your filters and you'll get pretty crappy production water for the first few minutes for the reasons highlighted in 1. above. A heads up for those folks who have their system plumbed directly to their ATO & allow it to be controlled by a float switch.

Other things worth noting after running the system over the years is that I don't trust the auto shutoff valve (ASO). I'm actually considering removing the thing as it will simplify the plumbing & probably make the RO membrane more efficient with one less restricting component. I tried using the float valve in my NSW make up container when the system was new but the waste water would always continue to run after the float valve closed. Played around with the ASO & considered getting a new one, but gave up on that idea since I'm just too nervous about the reliability of the device. I have no drain in my basement floor, so chance of a flood due to an iffy little device is enough for me to be content without the automation. I'm always at home when I produce water & use the timer on my oven as a reminder to check on things periodically. I've also installed a water detector on the floor & it's saved my bacon a couple of times.

It's useful to have clear housings for your sediment filters as they provide a visual indication of their condition. I've read that a vertical DI stage is better than a horizontal one, but can't verify that from personal experience. My DI stage is vertical & has a clear housing. The initial batch of DI media was colour changing so I guess a clear housing is useful there, although the DI media I have in there now is not colour changing. I'll rely on my TDS meter to tell me when it's exhausted. Carbon block also has a clear housing, but that's probably not required - I can't think of any useful visual indicator for this stage. Difference in price between the white & clear housings is not a deal breaker, so if in doubt, clear is good I suppose. I think the white ones may be more robust.

So yeah, get a water report, check your water pressure & order away based on that!

LOL yes i hear ya with the float valve. I plan on using one however . My system being servicing a 5 G space in my sump with a floating valve will be shut off when i leave home with a ball valve. the other 30G mixing bucket will also be shut off by that valve no water will be produced when i'm not there. Besides i work at home and when i go to bed they'll also be shut off by that simple valve. Both inspected in my routine daily inspection along with my 2 herbie drains 2minutes tops. Its shorter than a bowel movement....

[MarieH]

I live in Verdun, suburb of Montreal, my water is 148 tds from the tap. I got an aquasafe for price point and free ship. I bought the faucet adapter because I'm an apartment dweller. Tds is 000 after 7 stages. I don't mind shelling out for the resins once a year. I just find all the cartridges piled up together a bit of a bulky bother but the water is good and I think if there's more stages you can go longer between resins?

[Basile]

I was going to take max Cap spectrapure but the Vertex for $20 more as total automatic flush a booster pump and opperated by itself plug and watch is about it, so i'm going with that 100gph 4 stage.Thanks guys for your input.

[gregzz4]

Basile, what's your tapwater TDS ?