TDS meter/ RODI questions

[Justin1997]

So I have an RODI unit made the stupid mistake of not purchasing a TDS meter when I got the unit, cleaned my tank a few times and broke out in hair algae, so I've been using water from fish store for about a month now just bought myself a TDS meter. Rodi water is testing at 143ppm this means I have to change the filters right? If so which ones or do I change all?

 

[reef208]

So I have an RODI unit made the stupid mistake of not purchasing a TDS meter when I got the unit, cleaned my tank a few times and broke out in hair algae, so I've been using water from fish store for about a month now just bought myself a TDS meter. Rodi water is testing at 143ppm this means I have to change the filters right? If so which ones or do I change all?

How long have you owned the unit and when is the last time you changed any of the filters?

You'll need to change the DI resin, pre-filter, and carbon filter for sure.

 

[Justin1997]

It's a 4 stage unit bought it about 4 months ago I probably filtered like 60 gallons of product water through it during the first month never used it since, I've been buying jugs. Until today I bought myself a tds meter so I don't need to keep using jugs

 

[reef208]

Wow...that makes no sense being your unit is that new and having processed such little water through it.

What ro/di unit do you have? What TDS meter did you get? Also, did you check the TDS of your tap water for comparison?

 

[Justin1997]

Yea I got HM tds unit cost 42$ assuming it's pretty accurate, tap waters tests at 442. RODI unit is a puratek 4 stage

I do however rent where I'm living so I didn't want to cut pipes under sink to install, laundry sink is downstairs so this is how I have it rigged to sink

not sure if this makes a difference

 

[redfishbluefish]

You have to be testing the waste water line and not the "good" water side. A good membrane will typically be about 98 % efficient, with the DI cleaning up that last couple percent. Something's not right. Could you take pictures or diagram how you have it set up.


EDIT TO ADD: Oops! While I was typing you posted the pictures above. Let me see what I can see.

EDIT # 2: Here's what it should look like:

 

[reef208]

You have to be testing the waste water line and not the "good" water side. A good membrane will typically be about 98 % efficient, with the DI cleaning up that last couple percent.

That is a possibility still. Try testing the TDS on the rejection line just to make sure it's all assembled correctly.

Otherwise, perhaps you have a faulty membrane.

 

[Justin1997]

When I turn it on there's more product water coming out and barely any waste if any at all

 

[reef208]

When I turn it on there's more product water coming out and barely any waste if any at all

That sounds like you might have which line is which mixed up. Waste water usually has a lot of water coming out and clean water is slower.

 

[Justin1997]

I can change it but the pressure goes down usin this switch

than I get drops at a time to product and lots of waste

 

[reef208]

Did you check the TDS on the other line?

HM is a good meter, so shouldn't be an issue there.

 

[Justin1997]

Did you check the TDS on the other line?

HM is a good meter, so shouldn't be an issue there.

No water comes out from the waste line, I'll post a video here to show what's going on, the unit kinda has an odour too which seems unusual lol

 

[reef208]

Did the ro/di unit come assembled with all the hoses already attached or did you have to put all the hoses in? I'm feeling pretty confident your issue is with either with the hoses being connected wrong or maybe the membrane.

Do you have the instruction manual that you could compare to for ensuring the hoses are all connected to the right places?

 

[redfishbluefish]

This is your waste line. That valve needs to be completely closed to make good water. You only open it for a minute or so to flush the membrane.

 

[Justin1997]

Well this isn't allowed me to upload my video, I put it all together

 

[Justin1997]

This is your waste line. That valve needs to be completely closed to make good water. You only open it for a minute or so to flush the membrane.

I must have this hooked up wrong with this close my only tubes would be product and source, not sure where the waste comes out of

 

[reef208]

Could you post a picture of the back side of the unit so I can see how those hoses are connected?

 

[Justin1997]

mine says drain as well but you say to keep that fully closed there is no other waste line

 

[Justin1997]

Just opened that valve completely waste water tested at 410, product 420

Completely closed is 410 - product

Halfway open is 242

 

[Justin1997]

Just opened that valve completely waste water tested at 410, product 420

Completely closed is 410 - product

Halfway open is 242

No waste 70 psi on the gauge I get 175 product water