RODI Filtration Help!!!

[Slushi]

In search of help!

Found out my natural city water TDS is 561....I have an RODI 4 stage 100 GPD set up. My coral aren't looking too healthy. I have attached some photos of my system, what it looks like a few days after I replaced the three filters (sediment, carbon, DI Resin) as well as the outcoming TDS reading. It is still very high at 308 ( outcoming). I have been thinking of putting a gauge to help the pressure. I don't know what my current PSI is, and I do not have a TDS meter on it, just a TDS pen reader. If you can suggest ANY upgrades that will help me produce lower TDS with links, that would be great! my coral are not looking to healthy and im assuming that is due to my water quality. All other parameters seem to be within normal range. I am using Seachem Prime, after I make water already.

Also, I have a spare gauge but not sure how or what I need to hook it up. Any thoughts on this?

Thank you all for your help!

 

[oceanslide]

With tds that high I would look into the bulk reef supply filters. You should run a 6 stage system, sediment filter, dual carbon blocks, ro, then 2 di stages.
And if you are using the color changing di resin, it looks like it’s time to change it.

 

[Aquavaj]

That doesn't sound right. The rejection rate after the membrane should be in the high 90s. Even a 80% rejection rate should yield around 112 tds. Your di should take it down to 0 but will go out fast due to the high incoming tds. You need to find out your water pressure and if it's around 65 then your membrane might be shot.

 

[Slushi]

With tds that high I would look into the bulk reef supply filters. You should run a 6 stage system, sediment filter, dual carbon blocks, ro, then 2 di stages.
And if you are using the color changing di resin, it looks like it’s time to change it.

How do I run a 6 stage? And I just changed this a few days ago and it turned colors immediately. I've only made five gallons of water. Everything I've purchased was from marine depot. Including their filters.

 

[Slushi]

That doesn't sound right. The rejection rate after the membrane should be in the high 90s. Even a 80% rejection rate should yield around 112 tds. Your di should take it down to 0 but will go out fast due to the high incoming tds. You need to find out your water pressure and if it's around 65 then your membrane might be shot.

Could it be possible I have one of the lines backwards? Or maybe a filter upside down? I'll work on getting the gauge going

 

[bblumberg]

Something is wrong with the plumbing, or the flush valve is open (if it has one). I don't know exactly what components your system has, but a decent RO membrane should give 95% rejection and I'd expect to get ~99% with a Dow Filmtec membrane. This should put your output water below 10 ppm and let your DI last for a while. As others have said, water pressure is an issue so get a gauge to check it. Or better still, see below and buy the right RODI unit that comes with one...

In my opinion, this system is not adequate for water with the PPM yours has. You need at last one sediment filter, 2 carbon blocks, the RO and at least 2 DI filters. You can upgrade this one with more parts, but I'd buy one from BRS or Air Water Ice configured correctly.

 

[Aquavaj]

Could it be possible I have one of the lines backwards? Or maybe a filter upside down? I'll work on getting the gauge going

No they can go in either direction. Make sure the canisters are screwed on tight. Also check if the membrane is seated in the correct direction and in all the way. If you're getting adequate pressure after checking all of this then the membrane might be bad.

 

[Saltyreef]

Make sure your waste and RO supply arent going backwards into your DI resin. That would make the color chsnge immediately lol

 

[Reef.]

Have you unwrapped the filters?

I’m not being patronising , as I never did when I set up my RO system.

 

[Opus]

You do not need a 6 stage RO unit just because you have high tds. The RO membrane does all the work on lowering tds. The prefilters are just there to protect the RO membrane. If you are trying to lower a certain chemical such as chloramines or a metal then 2 carbon filters may be warranted, with one of them specializing in what you are trying to get rid of. If your RO membrane is old or if your carbon filter was old and it wasn't taking out the chlorine (assuming you have it in your source water), the chlorine will eat holes in the RO membrane. Water pressure could be an issue but doubt it would be giving you that kind of tds reading. Were you getting the 300+ tds reading before you changed the prefilters and DI?

If your RO membrane is fairly new, did you install it yourself. As stated it could be installed wrong.

 

[Slushi]

Make sure your waste and RO supply arent going backwards into your DI resin. That would make the color chsnge immediately lol

How do I know if this is the case? Can you tell from the pics?

 

[Slushi]

Have you unwrapped the filters?

I’m not being patronising , as I never did when I set up my RO system.

Yes all unwrapped yes

You do not need a 6 stage RO unit just because you have high tds. The RO membrane does all the work on lowering tds. The prefilters are just there to protect the RO membrane. If you are trying to lower a certain chemical such as chloramines or a metal then 2 carbon filters may be warranted, with one of them specializing in what you are trying to get rid of. If your RO membrane is old or if your carbon filter was old and it wasn't taking out the chlorine (assuming you have it in your source water), the chlorine will eat holes in the RO membrane. Water pressure could be an issue but doubt it would be giving you that kind of tds reading. Were you getting the 300+ tds reading before you changed the prefilters and DI?

If your RO membrane is fairly new, did you install it yourself. As stated it could be installed wrong.

Yes I changed this out myself. From the pics, does it look like it's installed incorrectly? They're all pretty much brand new. I just recently got a tds meter so I didn't know what it was prior. But assuming high because any time I mixed my instant ocean salt, I was pulling out 20 alk for no reason. On every new batch. Now I believe that to be because of the tds

 

[Saltyreef]

Yes all unwrapped yes

Yes I changed this out myself. From the pics, does it look like it's installed incorrectly? They're all pretty much brand new. I just recently got a tds meter so I didn't know what it was prior. But assuming high because any time I mixed my instant ocean salt, I was pulling out 20 alk for no reason. On every new batch. Now I believe that to be because of the tds

High tds in your topoff water isnt going to equate to high alkalinity in your tank.

What are you using to measure salinity?

 

[Opus]

Yes all unwrapped yes

Yes I changed this out myself. From the pics, does it look like it's installed incorrectly? They're all pretty much brand new. I just recently got a tds meter so I didn't know what it was prior. But assuming high because any time I mixed my instant ocean salt, I was pulling out 20 alk for no reason. On every new batch. Now I believe that to be because of the tds

Installation looks ok from what I can tell. You can do a ration test to see if that is correct. Take a measuring cup and time the water coming out of the waste side and then the good water for the same amount. So if it takes 3 minutes to get a cup of good water it should take around 1 minute or less for bad water. You should be running somewhere between a 3 to 4 ratio of bad water to good water production.

You should also reseat your RO membrane. Take out the ro membrane and then push it back in. Push it hard, it takes some effort to get it pushed all the way in.

 

[Opus]

High tds in your topoff water isnt going to equate to high alkalinity in your tank.

What are you using to measure salinity?

He said high alkalinity in freshly mixed salt water, not topoff or in his tank.

 

[Slushi]

High tds in your topoff water isnt going to equate to high alkalinity in your tank.

What are you using to measure salinity?

Hanna checker

 

[Saltyreef]

He said high alkalinity in freshly mixed salt water, not topoff or in his tank.

Thanks for the clarification. Even still. My alk has never skyrocketed to 20dkh in a fresh mixed batch of salt water using tap water....

 

[MTBake]

Are you sure this is hooked up correctly? Where's the yellow line coming from?

 

[Saltyreef]

OP, have you done a tap water test to see what youre dealing with as far as contamination?

Aside from TDS, do you know your taps PH, hardness, co2 content, chlorine level? Chloramine level if applicable?

 

[Opus]

Thanks for the clarification. Even still. My alk has never skyrocketed to 20dkh in a fresh mixed batch of salt water using tap water....

Just depends on what is in the water. My water is very hard. Everything around my freshwater tank has a hard crust on it because of the stuff that has come out of the water.