TDS creeping after 4 weeks

Spare time · Sep 13, 2021

Mindblock769 said:
I noticed an air gap at the top of the di resin. I removed the cartridge and slammed it down a few times to pack it and was able to push the filter a half inch or so down. I'm reading 29ppm after the DI now. So there's still some sort of issue with the membrane. Is 29ppm safe for partial water change? Or at least for my ATO?

Ah sometimes if the resin isn't packed tightly and you see it tumbling, this can shorten the lifespan of the resin. Regardless, you shouldn't have as high of a tds for water coming out of the membrane (at least from my experience)

Spare time · Sep 13, 2021

Booster pumps will raise the pressure if you need to do so

Mindblock769 · Sep 15, 2021

I guess my city work just sucks, and 4 stages isnt enough.

Installed all new filters, and reading 13ppm after RO and 11ppm after DI.

Ive attached a 2019 water report I found.

Suggestions? 5/6/7 Stage? Booster?

KStatefan · Sep 15, 2021

What filters did you replace? A new DI resin filter should not be 11. A booster pump would help the rejection but right now it seems like it is the DI that is not working correctly

Mindblock769 · Sep 15, 2021

KStatefan said:
What filters did you replace? A new DI resin filter should not be 11. A booster pump would help the rejection but right now it seems like it is the DI that is not working correctly

All 4. Carbon, sediment, RO and DI

KStatefan · Sep 16, 2021

Something wrong with your DI stage. It should be able to take the 13 tds ro water down to zero. Can you post a picture of your system? What di filter did you purchase

Mindblock769 · Sep 16, 2021

KStatefan said:
Something wrong with your DI stage. It should be able to take the 13 tds ro water down to zero. Can you post a picture of your system? What di filter did you purchase

This one from Amazon. Since it was my fastest option. Btw, thank you for sticking around to try to help!

Aquatic Life Reverse Osmosis 10” Replacement Filter Cartridges Kit - Includes Carbon Block Filter, Sediment Cartridge, 100 GPD Membrane and Mixed-Bed Color Changing Deionization Resin

Mindblock769 · Sep 16, 2021

Looks like the link didnt show up, heres a picture.

Mindblock769 · Sep 16, 2021

So an update I'm reading 0ppm again. After replacing the filters and still seeing 12ppm I removed the DI and found the top of the DI canister was damaged. I took my old DI and replaced the resin with BRS resin and now I'm reading 0ppm.

I guess my first RO filter was defective or my water just really is that dirty idk. I will keep a close eye in it and hopefully not have to replace RO filters every few weeks.

KStatefan · Sep 17, 2021

That is good.
A membrane should last a long time 2 - 5 years for a filmtech.
You water system looks like they use chlorimines which is harder for the carbon to remove. I like to run two carbons and change the first one often. I use a cheap 1 micron carbon that I change at 2000 gallons used then a 0.5 micron.

Buckeye Hydro · Nov 30, 2021

Yeow. Let's go through the issues 1 by 1.

An RODI system with a single membrane, single DI stage, and inline TDS meter should be configured with a THREE probe meter. You're seeing the problem with anything less right now. A 3-probe meter allows you to read your 1) incoming feed water; 2) permeate (aka RO water); and 3) DI water. The most straightforward way of doing this is with a three probe TRM1 meter https://www.buckeyehydro.com/trm1-tri-inline-tds-meter/. Because you already have a single probe meter, you'll want to supplement that with a TWO probe DM1 https://www.buckeyehydro.com/dm1-dual-inline-tds-meter/

Your first DI cartridge was poorly packed. If I were you I'd ask your vendor for a refund. When DI cartridges are not packed tightly enough, after a bit of use you'll see an airspace at the top of the cartridge - your pic earlier in the thread shows this. When the cartridge isn't packed tightly enough, the DI resin bed will fluidize in short order, the cation and anion resin will separate; you'll no long have "mixed bed resin," and you'll see what looks like a color change at the top part of the cartridge. Your pic earlier in the thread shows this. The treatment you'll get from the DI cart once this has happened will be degraded, even with new resin.

The damage you show inside the neck of the DI cart is irrelevant and will not affect the TDS reading coming from the DI cart. However, because I can't see a nice full circle indentation from the knife edge seal in the white gasket, I'm wondering if the DI cart wasn't centered and you had some flow bypassing the gasket. This would definitely affect the TDS in your DI water.

As noted above, your tap water contains chloramine. Your system is not configured ideally to deal with that. This situation can be addressed easily. BTW - the carbon block that you bought in the kit from amazon is a super low-end block with very low capacity. I'd not recommend it for chlorine, let alone chloramine.

Russ