RO/DI question

WinterSun01

In Memoriam
I've got a Airwaterice 5 Stage (not including the DI) that I need to replace the filters on. I already know the RO membrane I need, but what is the best resin/filter to run in the other 4, and in what order? Thanks
 
I order the 5 stage replacement from Bulkreefsuppply.. $35 for a complete set believe, DI included.
 
I'd also get a extra sediment filter or two. I usually replace those every 2-3x between DI changes
 
Yeah if you get a refillable DI cartridge you could run that after your sediment/carbon filters.
 
Wow, thanks everyone haha! My next question is, can I run a DI filter in one of the 4 stages before the RO membrane?

I highly suggest against this. The purpose of the membrane it to be the "workhorse" to bring down the TDS. The DI resin is to just polish off the good water coming out of the membrane. If the DI resin is place before the membrane you'll burn through A LOT of resin unnecessarily.
 
Couldn't have said it better myself. +1

I highly suggest against this. The purpose of the membrane it to be the "workhorse" to bring down the TDS. The DI resin is to just polish off the good water coming out of the membrane. If the DI resin is place before the membrane you'll burn through A LOT of resin unnecessarily.
 
the workhorse is the most expensive component.. you want to protect it...

that is the purpose of the 'pre filters'.

the finer the prefilter the more often / quicker it will clog...

you can use a 10 micron filter in stage one, then a 5 micron in stage two...(and three if you ahve)...

then the RO membrane...


if you have a carbon filter after that, you can change it.. or not. or take it out.. it dont matter.. that is for drinking water use... or jsut a mild polish for your tank top off water.. but really not necessary

the Resin is also expensive, and you want to protect it too..

you can run tap water thru Resin and it will work great.. probably bring the TDS down to ZERO, but it will be exhausted after the first use... so, to make it last longer, you want to use the least amount of TDS water thru it as possible..

which is why the TDS should be last in teh series and the last filter before the tank...


If you have a pressure cannister, you should put the resin AFTER the cannister.. or again, the last thing the water sees before your fish tank...

you really dont want to store dionized water in a metal tank as it is slightly corrosive...

also, stored water will get contaminated so some of what you removed with your filter may come back in the cannister.

the other bad thing about cannisters is that it pushes the water faster thru the DI Resin, and sometimes it/the water, may not have enuf 'dwell time' / contact time with teh resin for it to work properly


Call Russ up at BRS, he will be glad to walk u thru it...


gl
 
There is more to correct, but the bold section is completely wrong. Miss information is damaging to the community, let's not spread it.

Carbon removes chlorine which protects the membrane making it a critical component of any RO/DI system.


the workhorse is the most expensive component.. you want to protect it...

that is the purpose of the 'pre filters'.

the finer the prefilter the more often / quicker it will clog...

you can use a 10 micron filter in stage one, then a 5 micron in stage two...(and three if you ahve)...

then the RO membrane...


if you have a carbon filter after that, you can change it.. or not. or take it out.. it dont matter.. that is for drinking water use... or jsut a mild polish for your tank top off water.. but really not necessary

the Resin is also expensive, and you want to protect it too..

you can run tap water thru Resin and it will work great.. probably bring the TDS down to ZERO, but it will be exhausted after the first use... so, to make it last longer, you want to use the least amount of TDS water thru it as possible..

which is why the TDS should be last in teh series and the last filter before the tank...


If you have a pressure cannister, you should put the resin AFTER the cannister.. or again, the last thing the water sees before your fish tank...

you really dont want to store dionized water in a metal tank as it is slightly corrosive...

also, stored water will get contaminated so some of what you removed with your filter may come back in the cannister.

the other bad thing about cannisters is that it pushes the water faster thru the DI Resin, and sometimes it/the water, may not have enuf 'dwell time' / contact time with teh resin for it to work properly


Call Russ up at BRS, he will be glad to walk u thru it...


gl
 
you can use a 10 micron filter in stage one, then a 5 micron in stage two...(and three if you ahve)...

Use this approach of decreasing pore size on successive filters only for sediment filters, not carbon filters


If you have a pressure cannister, you should put the resin AFTER the cannister.. or again, the last thing the water sees before your fish tank...
If you have a pressurized storage container, do not deliver that water to the DI stage



A last but not least,
Call Russ up at BRS, he will be glad to walk u thru it
This Russ is at BFS!:rollface:

Russ
 
oh crap.. sorry, BFS

thanks russ... ah, yes...(edited after i re read my original message).. i mixed up the pressure cannister thing.. you should not feed teh resin from the pressure cannister due to the dwell time... but you still shouldnt 'store' dionized water in metal cannister? and or expect stored ZERO TDS water to come out of 'storage' with zero TDS?

are you suggesting that a pressure cannister shouldnt be using on a REEF system where the output is expected to be ZERO TDS?

or can a Pressure cannister be used on a REEF system, but it should be the last think in teh 'filter system' and they output will still be ZERO?

hopefully that made sense...and sorry for flip flopping on the message in my original message...



also, the 'pre filters' are the 'sediment filters' arent they

btw: can you comment on the use of the typical final stage of a '5 stage' filter, isnt that a carbon filter? and isnt it mainly for smell/taste for 'drinking water'? do we Reefers need it? or does it add anything to the filter system for reefers?

the poster above says it is 'important' But, i am thinking he is thinking of teh 'third or fourth stage on some filters' on the carbon / or newer 'cloramine' filters? wouldnt those be 'before' the RO membrane?

or does it not matter where that carbon prefilter is located?

and as for posting MIS INFORMATION??? dude... seriously.. more then 70% of whatever posted is MIS INFORMATION... but folks tend to post what they know or think they know until corrected..

what is bad for the community is to KNOWINGLY post mis information, and or to try to pretend you are MS. MANNERS of the internet world... so, please,,, take a breath... relax... and enjoy, be humble, ask questions... live, and learn..

you will be much happier.. i know i am...
 
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oh crap.. sorry, BFS
No worries!

you should not feed teh resin from the pressure cannister due to the dwell time...

The flow rate is one issue, but at least as important is that the TDS of RO water in a pressure tank will be much higher than the TDS of RO water straight from the RO.

you still shouldnt 'store' dionized water in metal cannister?
Right

and or expect stored ZERO TDS water to come out of 'storage' with zero TDS?
right

are you suggesting that a pressure cannister shouldnt be using on a REEF system where the output is expected to be ZERO TDS?
We use them on our Reef/Residential systems where the RO water goes to a pressure tank and then on to a drinking water faucet, AND RO water from the pressure tnak NEVER goes to the DI stage.


also, the 'pre filters' are the 'sediment filters' arent they
"Prefilter" means all the filters that come before the membrane, in order of water flow.


btw: can you comment on the use of the typical final stage of a '5 stage' filter, isnt that a carbon filter?
This one is a hoot! About the only place you'll ever see this: Prefilters->RO->DI->taste and odor (GAC) filter is on misconfigured systems common on a famous auction web site. If you see this configuration, I'd recommend not buying it. The water is alreeadt as clean as the misconfigured system can make it after the DI - there is no need to run it through more carbon. The other thing you'll see on most of these systems is horizontal DI stages. Again - if you see this, its a sign of a poorly configured system.



Carbon filters are a critical prefilter because nearly all of the membranes used in this hobby are "TFC" membranes that do not tolerate exposure to chlorine well.

Russ
 
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.
 
There is more to correct, but the bold section is completely wrong. Miss information is damaging to the community, let's not spread it.

Carbon removes chlorine which protects the membrane making it a critical component of any RO/DI system.

He's talking about a carbon filter after the membrane...you are also spreading the misinformation, fella.
 
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.

DI AFTER the membrane!!!!!!!!!!!!!!!!!!!

Probably that fourth canister is plumbed post-membrane, but only you can confirm or deny that.
 
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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?

DI AFTER the membrane!!!!!!!!!!!!!!!!!!!

Probably that fourth canister is plumbed post-membrane, but only you can confirm or deny that.
 
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