Ro help

Mr. Gonzalez · Jan 10, 2023

Need help with my ro. I searched and read other threads but now confused Korean than ever. I switched my membrane. Do I need to run off water before I start using the ro. Also I have no waste going out and not sure what is going on. All the lines are correct. I have new di that is a month old, carbon is new, and sediment filter is new. It's a 4 stage aqua fx system. Tds going in is 450 coming out is 113. Psi is 50. Water coming out way to fast. I purchased a membrane from Amazon for 100 gpd but not sure it was the right one. Any help is appreciated.

blaxsun · Jan 11, 2023

Yes, you typically need to run a set amount of water through the RO membrane every time you replace it (the manual for your RO system should indicate how much). You don't want to run your DI resin filter during this.

Mr. Gonzalez · Jan 24, 2023

so I have changed everything new. Did a 30 gallon run off work the membrane not connected to anything. Still having issues with my tds coming out high. Also no waste water is coming out still. Now my D.I. resin is halfway depleted. Really need help on this.

Crofty · Jan 24, 2023

Mr. Gonzalez said:
so I have changed everything new. Did a 30 gallon run off work the membrane not connected to anything. Still having issues with my tds coming out high. Also no waste water is coming out still. Now my D.I. resin is halfway depleted. Really need help on this.

If you're not getting waste water then it sounds like your RO membrane is compromised and leaking. It would explain the high TDS and also why your DI resin is getting used up so fast.

Edit: could be a bad seal on the RO as well

EeyoreIsMySpiritAnimal · Jan 24, 2023

Crofty said:
If you're not getting waste water then it sounds like your RO membrane is compromised and leaking. It would explain the high TDS and also why your DI resin is getting used up so fast.

Or it's plumbed wrong...

Mr. Gonzalez · Jan 24, 2023

Erin1971Texas said:
Or it's plumbed wrong...

I connected everything exactly the same as before. Took pictures and all. Also noticed my pressure dropped from 60 to 50 psi. Tds going in is 450-500 ppm.

EeyoreIsMySpiritAnimal · Jan 24, 2023

Mr. Gonzalez said:
I connected everything exactly the same as before. Took pictures and all. Also noticed my pressure dropped from 60 to 50 psi. Tds going in is 450-500 ppm.

What's the TDS coming out of the membrane?

EeyoreIsMySpiritAnimal · Jan 24, 2023

Also, check to see that the membrane was installed correctly (not backwards) and that it's seated properly.

Mr. Gonzalez · Jan 24, 2023

Erin1971Texas said:
What's the TDS coming out of the membrane?

135 after it has run through everything. Also verified with a second tds tester and it reads 134.

EeyoreIsMySpiritAnimal · Jan 24, 2023

Mr. Gonzalez said:
135 after it has run through everything. Also verified with a second tds tester and it reads 134.

That's not what I asked.
What is the tds after the membrane?

Mr. Gonzalez · Jan 25, 2023

Erin1971Texas said:
That's not what I asked.
What is the tds after the membrane?

I'm confused on that question then. How do I get that? I appreciate the help yall. I've been at this for a few days just stumped.

EeyoreIsMySpiritAnimal · Jan 25, 2023

If your membrane has a rejection rate of 90-95, then TDS after the membrane should be around 25.

EeyoreIsMySpiritAnimal · Jan 25, 2023

Mr. Gonzalez said:
I'm confused on that question then. How do I get that? I appreciate the help yall. I've been at this for a few days just stumped.

You need to disconnect the tube at the spot it enters your first DI canister and test the water coming out of the membrane.

Mr. Gonzalez · Jan 25, 2023

Erin1971Texas said:
If your membrane has a rejection rate of 90-95, then TDS after the membrane should be around 25.

Ok so do I disconnect the line after the membrane and read the tds?

EeyoreIsMySpiritAnimal · Jan 25, 2023

Mr. Gonzalez said:
Ok so do I disconnect the line after the membrane and read the tds?

Don't disconnect where it comes out of the membrane or you'll have no way to control the water... Disconnect the other end of that tube -where in enters the DI canister.

** Let it run into a bucket, etc, for a minute and then collect some in a smaller container and measure TDS from that. You do this just in case there's any buildup coming out of the membrane when it starts up.

Mr. Gonzalez · Jan 25, 2023

I disconnected it at this end not sure if this is correct. So water runs through the sediment the carbon then the membrane and then is coming out that line I have disconnected. It's reading 405 ppm.

EeyoreIsMySpiritAnimal · Jan 25, 2023

Mr. Gonzalez said:
I disconnected it at this end not sure if this is correct. So water runs through the sediment the carbon then the membrane and then is coming out that line I have disconnected. It's reading 405 ppm.

I cannot tell if this is the correct line or not, but if your TDS after going through the membrane is still that high, either you have a bad membrane, you installed it backwards, or it's not seated properly.

What brand is your RODI ?

EeyoreIsMySpiritAnimal · Jan 25, 2023

Erin1971Texas said:
I cannot tell if this is the correct line or not, but if your TDS after going through the membrane is still that high, either you have a bad membrane, you installed it backwards, or it's not seated properly.

What brand is your RODI ?

You might just need to contact the manufacturer.

Mr. Gonzalez · Jan 25, 2023

Erin1971Texas said:
You might just need to contact the manufacturer.

I bought it through Amazon. I've purchased from in the past before from same seller and this is the first time I've had this occur.

EeyoreIsMySpiritAnimal · Jan 25, 2023

if your TDS after going through the membrane is still that high, either you have a bad membrane, you installed it backwards, or it's not seated properly.

Take apart the housing and check that the membrane is installed correctly and if that doesn't fix it, replace the membrane with a new one. If the replacement works, then contact whoever you bought the bad one from and ask for a refund.