RO/DI filter bad?

[Jon Fishman]

I went cheap (in hindsight I upgraded tank size, and wish I had gone bigger) but I got this RODI filter:

https://www.amazon.com/gp/product/B00LKF3TCA/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

I got a TDS tester and was showing 145 or so tap, and 0 after filter.

I ran 40 gallons or so, and I'm already showing 1-3 TDS when I test now. Is that normal? I am inclined to think running my reef on 1-2 TDS water would be "o.k." but I'm sure someone will tell me how absolute zero is the only way.....

Either way, is this a case for returning the filter and getting a different one? I'm kinda at a loss on this thing.

Overall, the fact that I can measure a noticeable difference is nice, but if the filter goes south quickly, I need a new solution.

 

[Montiman]

Do you know the water pressure? Is the DI colorchanging? Which TDS meter are you using?

 

[Jon Fishman]

I ordered a gauge but haven't gotten it yet. Kinda forgot about it.

I got this TDS tester:

https://www.amazon.com/gp/product/B07H578WWT/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1


If the DI is the clear filter-tube, then "yes" it's getting brown-ish I think at the bottom 2 inches or so. Not home to confirm.

 

[Ruben's Reef]

I have the same unit but made by Aquaticlife. My tap water is 168 and after the membrane came to 1 tds and after the DI is 0. I'm been running that system since last June and now my tds after membrane is 4 but still getting 0 after the DI. I do 15 gallons every two weeks so basically is not much.

 

[Montiman]

Because you are using a drop in rather than an inline meter I wouldn't worry. As soon as RO water is made it "Grabs" TDS from the air. It is very hard for 0 TDS water to stay 0 for long. If you use an inline meter you can see the reading before the water is exposed to dirty air or containers.