RO/DI question

[Buckeye Hydro]

Russ, why only do the step-down in pore-size with sediment filters and not the carbon blocks?

You want the pore size of your carbon cart(s) to be about the same size (or larger) than the smallest pore zize on any of the sediment filters. This keeps the carbon block from acting like a sediment filter. They well trap sediment, but you want the block(s) to chemically treat VOC's like chlorine, rather than getting loaded up with sediment.

Russ

 

[Buckeye Hydro]

Thanks, picked up this RO/DI unit used and that is what the previous owner did...The last stage is the DI (Plumbed to the ro membrane after the third stage, then out of the ro membrane to the 4th stage and exits from there) Thanks for the help everyone...

Although now I am having issues with the ASOV, the instructions say to let it run for one hour (minus the di stage) to clear out all the sediment, but my ASOV keeps kicking on and shutting it off..what do I do to prevent this?

Check to make sure whatever valve you have at the end of the DI output tube isn't leaking at all, and if you have a float valve, make sure it isn't bouncing around in turbulent water. Also check to make sure the check valve in the permeate port is working.

Russ

 

[letsgofishin]

FIRST OFF, my BAD.... i love bulkreefsupply too, so dont get me wrong, but RUSS, (the guy who has been helping us here in this discussion is BFS,, BUCKEYE FIELD SUPPLY..


so, not sure who or where or what you got as far as your filter... also, your next message says it is used.. so again, not sure if you got the filter from BRS, or used from some guy..

I am sure Russ will help you out, but maybe you will know where to get your next filter?

good luck,


(and sorry russ)




oh, so, now i understand you dont reccomend the use of pressure tanks for REEF systems, only for dual use filters, i.e. drinking and reef filters



I would like to get a poll going to find out how many folks use thier presure tanks for thier reefs..???

and follow up with where is your pressure cannister as far as in the filter? i.e. before the DI cannister or after?



for the record, mine is before teh DI resin, and i still have zero tds ouput, but maybe use up the resin quicker? (I also have dual di resin chambers) both vertical

Ok, I just received my BRS 5 stage filter replacement that everyone was recommending (http://www.bulkreefsupply.com/store...5-stage-standard-replacement-filter-kit.html#) I'm not sure if they messed up my order, but the link shows I was supposed to get a .01 micron carbon block but I didnt get one.

Here's what I got.

1-Matrikx CTO plus 0.6 micron
1-5 micron
1-purtrex 05 micron
1-color changing di resin

My question is, if I am not supposed to put the DI resin before the RO membrane, shouldnt there be one more micron filter?

There is 4 canisters below the ro membrane, so If I don't put DI resin in the fourth...what goes in it? Thanks.

 

[WinterSun01]

Alright, now my third question. everything is going well ( I think) I've made about 20 gallons so far, the Input TDS meter is showing 490 in, and 0 out.

But when I test the TDS with my hand held (I've got two different hand helds) they are showing between 50-110 between each jug (5 gallon jugs)

What do I do now?

 

[solitude127]

To get the most accurate reading is to test the water in a glass cup. Plastic containers will usually leach TDS

 

[Buckeye Hydro]

You really can't get accurate TDS reading bu dipping your TDS meter in a "storage container." Remember these meters read in part per million (ppm), so even the slightest little "contamination" will show up on the meter.

Some plastic containers are difficult to get absolutely clean, and although they appear clean, they are not. An easy standard approach is to use a drinking glass as a sample container - use one right out of the dishwasher. Obviously, keep your fingers away from the inside surface of the glass.

Calibrate your meter. Use a calibration fluid generally in the range of the tds measurements you'll be taking. Some meters require a specific tds calibration fluid (e.g., 800 ppm), regardless of the tds levels in your samples.

Be careful with how you take your samples. Let's say you intend to measure the TDS in your 1) DI water, 2) RO water, and 3) tap water. Start with the cleanest of the three - the DI water. After letting the system run for a sufficient period of time that you are sure the tds levels have stabilized (to assure you are not measuring tds creep water), rinse the sample container two or three times with the water you intend to sample, and then fill the sample container with sufficient DI water to take a reading.

Now on to the RO water. The water we are interested in here is the permeate – i.e., the water that has been purified by the RO membrane – not the waste water. Make sure you understand which is which before taking the sample. Most RODI systems other than Buckeye Systems are not plumbed to facilitate taking a sample of the permeate. If that is the case, you’ll need to unhook some tubing – likely where the tubing attaches to the “in” port on the DI housing in order to take this sample. This is inconvenient for many people, and we find that people never do it. They report only the tap water TDS and the DI water TDS. Contact Buckeye if you need guidance regarding installing a couple of extra fittings and tubing to facilitate measuring the TDS of the RO water (permeate). When you take the sample, follow the same procedure described above – use a clean sample container, assure you are not measuring TDS creep water, rinse with the permeate several times before taking the sample, and use a calibrated meter.

Use the same approach to collect and measure your tap water as well.

Russ

 

[Buckeye Hydro]

oh, so, now i understand you dont reccomend the use of pressure tanks for REEF systems, only for dual use filters, i.e. drinking and reef filters

Right - the idea is to only deliver to the DI the lowest TDS water possible - and that rules out water from a pressurized tank.

I would like to get a poll going to find out how many folks use thier presure tanks for thier reefs..???

That would be interesting. I think very few people understand this issue, especially those new to the hobby who are focused on getting the lowest cost RODI systems who tend to think they are getting a good value with partially retrofitted drinking water systems often sold on ebay

for the record, mine is before teh DI resin, and i still have zero tds ouput, but maybe use up the resin quicker?

Right.

Russ

 

[ReefMeister2]

Russ,
KUDOS for taking the time (and God only knows, a Hero-level of patience!) to answer all these questions. You are awesome

Even though I consider myself an "advanced knowledge" hobbyist in terms of plumbing and RO/DI subjects, I still learn something new everyday. that being said, this thread is absolutely crucial to correcting an incredible amount of misinformation out there (some even innocently spread myself).

One that I never knew before. but makes logical sense, is to not use a bladder tank (pressurized storage tank) to feed the DI stage. I am guessing that this is a relative subjective reccomendation, in that it all depends on the cost vs. convenience issue.

In other words, if you want the convenience of using a pressurized storage vessel AND don't mind the cost of changing resin a little more often, then this should be perfectly acceptible, yes? I guess my real question is, does the bladder tank really leach that much TDS to "significantly" burn through the DI resin that much faster?

Secondly, I've read this question many times (said in so many ways) but have yet to see a direct answer: What is an appropriate filter or stage to use AFTER the bladder tank so that our drinking water is of best possible quality? I've seen the little weanie filters all over the place but wouldn't a full size carbon filter block be that much more effective? (Especially considering that the carbon filter block is really no more expensive than the little weanie filters) the only disadvantage being having to mount another full size canister to deal with, yes?

Sorry in advance if my rambling is confusing and going in different directions.
My mind works in mysterious ways, LOL

(Edit]:
OHHHH, and one last thing:
PLEASE comment on your personal reccommendation about "drinking DI water" (Safe or Not Safe?) Is it Ok if cost is not a factor? I personally like the "crisp" taste of DI water but have been thwarted from doing so since I can't store DI water in our pressure tanks (which feed the fridge, ice maker, multiple faucets, etc.) I've heard the medical concerns that it may tend to absorb minerals from your body, etc. but unless you drink ONLY DI water, exclusively, I question the validity of this concern.

 

[Buckeye Hydro]

One that I never knew before. but makes logical sense, is to not use a bladder tank (pressurized storage tank) to feed the DI stage. I am guessing that this is a relative subjective reccomendation, in that it all depends on the cost vs. convenience issue.

In other words, if you want the convenience of using a pressurized storage vessel AND don't mind the cost of changing resin a little more often, then this should be perfectly acceptible, yes? I guess my real question is, does the bladder tank really leach that much TDS to "significantly" burn through the DI resin that much faster?

I guess there are few absolute truths re this topic. In the same way, you could say "I don't like waste water, but don't mind buying new membranes, so I closed my waste water valve...

If what you are after is convenience - that is, having a lot of DI water quickly when you need it, I think it is hard to argue against using an unpressurized DI storage container.

What is an appropriate filter or stage to use AFTER the bladder tank so that our drinking water is of best possible quality? I've seen the little weanie filters all over the place but wouldn't a full size carbon filter block be that much more effective? (Especially considering that the carbon filter block is really no more expensive than the little weanie filters) the only disadvantage being having to mount another full size canister to deal with, yes?

In most instances, you shouldn't have any filter after the DI stage. When it leaves the DI it is as clean as your system can make it. When we retrofit those low cost, mis-configured, ebay systems for customers, we routinely remove those inline taste and odor (GAC) filters that are often plumbed in after the DI.

If what you are after is drinking water, you'll want to tee off before the DI to access RO water.

Although you mentioned you like the taste of DI water, it sounds like what you've been drinking is DI water run through carbon (which I would no longer consider "DI water").

I'm not a medical doc so I'll refrain from posting my opinions (because that's all they are) re drinking DI water. Because I've never heard anyone say they like the taste of straight DI water, not sure why anyone would want to drink it...

The inline GAC ("taste and odor" filters) are used between pressurized storage tanks and faucets to remove the tase and odor the water picks up inside the bladder tank. And yes - a carbon block is a supeior filter the the small inline GAC, but it may be overkill in most, but not all, situations.


Russ

 

[WinterSun01]

Doesn't this eliminate the purpose of having a RO/DI unit if it just gets contaminated again once inside a storage bin? I don't fully understand the purpose then if it's almost impossible to completely clean the contrainer without it leaching some back in.

You really can't get accurate TDS reading bu dipping your TDS meter in a "storage container." Remember these meters read in part per million (ppm), so even the slightest little "contamination" will show up on the meter.

Some plastic containers are difficult to get absolutely clean, and although they appear clean, they are not. An easy standard approach is to use a drinking glass as a sample container - use one right out of the dishwasher. Obviously, keep your fingers away from the inside surface of the glass.

Calibrate your meter. Use a calibration fluid generally in the range of the tds measurements you'll be taking. Some meters require a specific tds calibration fluid (e.g., 800 ppm), regardless of the tds levels in your samples.

Be careful with how you take your samples. Let's say you intend to measure the TDS in your 1) DI water, 2) RO water, and 3) tap water. Start with the cleanest of the three - the DI water. After letting the system run for a sufficient period of time that you are sure the tds levels have stabilized (to assure you are not measuring tds creep water), rinse the sample container two or three times with the water you intend to sample, and then fill the sample container with sufficient DI water to take a reading.

My inline TDS meter is on the outlet right after the RO membrane, not the DI filter. It is to my understanding that the DI does not bring down the TDS, please correct me If I am wrong, thank you.

Now on to the RO water. The water we are interested in here is the permeate "“ i.e., the water that has been purified by the RO membrane "“ not the waste water. Make sure you understand which is which before taking the sample. Most RODI systems other than Buckeye Systems are not plumbed to facilitate taking a sample of the permeate. If that is the case, you'll need to unhook some tubing "“ likely where the tubing attaches to the "œin" port on the DI housing in order to take this sample. This is inconvenient for many people, and we find that people never do it. They report only the tap water TDS and the DI water TDS. Contact Buckeye if you need guidance regarding installing a couple of extra fittings and tubing to facilitate measuring the TDS of the RO water (permeate). When you take the sample, follow the same procedure described above "“ use a clean sample container, assure you are not measuring TDS creep water, rinse with the permeate several times before taking the sample, and use a calibrated meter.

Use the same approach to collect and measure your tap water as well.

Russ

 

[Buckeye Hydro]

Assuming the plastic isn't leaching any toxic materials that show up as TDS, what you're seeing in the storage container is likely the result of dust from the air and the like. The same substances that likely get into the open top of your aquarium everyday...

The RO membrane removes the bulk (90%+) of the TDS, and the DI resin removes the rest. So yes, DI resin removes TDS.

Russ

 

[ReefMeister2]

Im sorry, I wasn't suggesting using a carbon block filter after the DI, that would be silly.
I'm after the best quality drinking water (period) post RO-only and bladder tank.

Ohhh, here is a good question:
How often should people replace their pressure tanks? (or is there a reliable method of sanitizing them?)

 

[Buckeye Hydro]

I wouldn't replace it until it just doesn't work any more. You'll know it when you open your RO faucet to get a glass of water and it just dribbles out.

To sanitize:

 

[pciscott]

Great information, also if you mix salt in the containers you are checking for TDS you will throw off your test as any salt will show high TDS. I left a valve open on my mixing station and ended up backflowing some salt into my fresh water and ended up throwing out a bunch of good water until I figured this out. What I am saying is salt could very well be your contaminate.

Russ, do we have to do anything different to pull out chloromines as this seems to be a new mix that Southern California water companies are using? I have read that with high chloromines ammonia can get past the membrane any truth to this? Thank you for the expert advice and my next filter order will be coming your way.

 

[WinterSun01]

Got it, thank you very much for all the info. So I don't need to worry about the TDS showing from the container (Pretty sure it's not toxic) and worring that it's going to cause a huge algae bloom in my tank?

Assuming the plastic isn't leaching any toxic materials that show up as TDS, what you're seeing in the storage container is likely the result of dust from the air and the like. The same substances that likely get into the open top of your aquarium everyday...

The RO membrane removes the bulk (90%+) of the TDS, and the DI resin removes the rest. So yes, DI resin removes TDS.

Russ

 

[Buckeye Hydro]

Great information, also if you mix salt in the containers you are checking for TDS you will throw off your test as any salt will show high TDS. I left a valve open on my mixing station and ended up backflowing some salt into my fresh water and ended up throwing out a bunch of good water until I figured this out. What I am saying is salt could very well be your contaminate.

Anyone have a guess what the tds is of typical sea water? Hint: It is WAY higher than the probably 9999 limit of your TDS meter.

Russ, do we have to do anything different to pull out chloromines as this seems to be a new mix that Southern California water companies are using? I have read that with high chloromines ammonia can get past the membrane any truth to this?

We normally suggest that people consider no more that a 4 stage RODI, unless they are dealing with a specific water quality issue.... like chloramines for instance.

A second carbon prefilter either Catalytic GAC or a second good quality block is a good idea/good insurance if you have chloramines in your water, as contact time with the carbon is very important when trying to address chloramines. And yes, the ammonia released by the spliting of the chloramines will go through the membrane for the most part, and will be caught by the DI. So expect a shorter life span on your resin than you were seeing previously.

Thank you for the expert advice and my next filter order will be coming your way.

 

[letsgofishin]

not to beat the dead horse, but.. the other 'issue' with pressure cannister' is that the accelerated flow past the di resin... it is reducing teh contact time and 'dwell' time... so it isnt just a matter of adding more tds into the water that filterd by the ro membrane, only to be removed again..


and i had heard that you can take tap water and run it thru di resin and get zero tds but only once, myabe twice? is that true?

 

[Buckeye Hydro]

It all depends upon the TDS of the tap water. Some of our customers have 40 ppm tapwater - youd expect to be able to get about 125 gallons from a single DI cartridge.

We have other customers with 1200 ppm tap water - they would be lucky to get 5 gallons from 1 cartridge.

 

[ReefMeister2]

Russ,
May I ask,
Could you please describe the configuration you personally use for drinking water in your own house?

Second follow-up question:
If cost were not a factor, what in your opinion, is the ultimate drinking water setup/configuration? (within reason of course)

 

[letsgofishin]

Russ,
May I ask,
Could you please describe the configuration you personally use for drinking water in your own house?

Second follow-up question:
If cost were not a factor, what in your opinion, is the ultimate drinking water setup/configuration? (within reason of course)

isnt this the same question? assuming russ has the best money can buy???