TDS NOT 0 Help me find out why

[islandreef]

I have a six stage RO/RI Unit and cant seem to find out why I cant get my TDS to 0, Just changed all filter less than two weeks ago. Tried to purge at least 30 gallons through it already.

Goes Like this 1 Micron Sediment Filter -> 1 Micron Carbon Block Filter -> Pro Series Purple Cation DI Resin (1) -> Pro Series Anion DI Resin (2) -> Pro Series Mixed Bed DI Resin (3) Last stage is Silica Buster DI Resin.

My TDS meter says coming in its 43 After the Di Resins it drops to 1 then once it goes through the Silica Buster it goes up to 5. Very Confusing Help me out.

 

[Randy Holmes-Farley Verified Community Expert]

If it is newly set up, run a gallon or so through it to flush out stuff. If it has been running, I don’t know why that would be unless the silica buster is depleted.

 

[islandreef]

If it is newly set up, run a gallon or so through it to flush out stuff. If it has been running, I don’t know why that would be unless the silica buster is depleted.

Randy I appreciate you response. I have already ran 30 gallons through this into a brute container. Silica buster is also brand new.

 

[Uncle99]

Randy I appreciate you response. I have already ran 30 gallons through this into a brute container. Silica buster is also brand new.

My resins are last after RO.
Is there an RO in that group?
So, sediment, carbon, RO, (from 140 to 5)
Then DI from 5 to 0.

Maybe I just don’t read your post right.

 

[islandreef]

My resins are last after RO.
Is there an RO in that group?
So, sediment, carbon, RO, (from 140 to 5)
Then DI from 5 to 0.

Maybe I just don’t read your post right.

I dont get 0 TDS at all. RO/DI SYSTEM this is the current system I have. I added 3 more to it. Filters go like this.

Goes Like this 1 Micron Sediment Filter -> 1 Micron Carbon Block Filter -> Pro Series Purple Cation DI Resin (1) -> Pro Series Anion DI Resin (2) -> Pro Series Mixed Bed DI Resin (3) Last stage is Silica Buster DI Resin.

 

[Uncle99]

I dont get 0 TDS at all. RO/DI SYSTEM this is the current system I have. I added 3 more to it. Filters go like this.

Goes Like this 1 Micron Sediment Filter -> 1 Micron Carbon Block Filter -> Pro Series Purple Cation DI Resin (1) -> Pro Series Anion DI Resin (2) -> Pro Series Mixed Bed DI Resin (3) Last stage is Silica Buster DI Resin.

Ok,yup I’m not reading the post right.
Did you get zero before?
Or is this a new application?
Seems like a ton of resins.

 

[painter1982]

Do you have a different way of testing tds? Maybe the tester is the problem

 

[jsmkmavity]

You listed 6 stages twice now but still no ro filter. Not sure why you would have silica buster resin with all the other filters? Sometimes the resin can be defective.
Usually it would go thru a sediment filter then carbon block then ro membrane then sometimes another carbon for taste and odor then 1 or 2 di resin canister(s).

 

[Randy Holmes-Farley Verified Community Expert]

Where did you get the cartridges? High quality place?

What sort of source water? Well?

A mostly depleted silica buster could raise TDS.

When an anion or cation resin is operating, OH- or H+ is released from them, respectively. If both are not depleted, then the OH- and H+ combine to make water and the TDS can be zero.

If one of them is depleted, then H+ or OH- is being released, and that can actually raise the TDS relative to the incoming water because those two ions are far, far more conductive than any other ions in water.

The H+ or OH- should be caught by a working mixed bed. If you accidentally put an anion or cation in the last spot instead of the silica buster, or if the silca buster was depleted by the 30 gallons (could happen on high CO2 well water), then you might get nonzero TDS out of it.

 

[KStatefan]

It is not clear what you have the link you shared is a RODI but you do not list a membrane in your list.
Are you using a membrane or just carbon and DI resins?

 

[islandreef]

Where did you get the cartridges? High quality place?

What sort of source water? Well?

A mostly depleted silica buster could raise TDS.

When an anion or cation resin is operating, OH- or H+ is released from them, respectively. If both are not depleted, then the OH- and H+ combine to make water and the TDS can be zero.

If one of them is depleted, then H+ or OH- is being released, and that can actually raise the TDS relative to the incoming water because those two ions are far, far more conductive than any other ions in water.

The H+ or OH- should be caught by a working mixed bed. If you accidentally put an anion or cation in the last spot instead of the silica buster, or if the silca buster was depleted by the 30 gallons (could happen on high CO2 well water), then you might get nonzero TDS out of it.

All filters were purchased from Bulk Reef Supply

 

[islandreef]

This is what I posted in that link this is the system I used, I have added to it.

 

[islandreef]

It is not clear what you have the link you shared is a RODI but you do not list a membrane in your list.
Are you using a membrane or just carbon and DI resins?

There two membranes at the top of my unit.

 

[KStatefan]

There two membranes at the top of my unit.

So you have this?

1 Micron Sediment Filter -> 1 Micron Carbon Block Filter -> Membrane 1 -> Membrane 2 -> Pro Series Purple Cation DI Resin (1) -> Pro Series Anion DI Resin (2) -> Pro Series Mixed Bed DI Resin (3) Last stage is Silica Buster DI Resin

What is the tds before the first membrane and after the second membrane?

 

[islandreef]

Just doublechecked again and it seems it just needed to run a bit longer. Water coming in is at 38 Water going through Resin it at 0 now and water through silicate buster DI is now also 0. I really appreciate you guys giving me things to look through.

 

[Randy Holmes-Farley Verified Community Expert]

Sounds good,

Happy Reefing!

 

[jsmkmavity]

One thing i recommend if possible is to run any new carbon filters or media filters with the ro membranes bypassed for a while to get rid of any loose particles. I had a new carbon filter plug up a membrane once years ago.