1PPM TDS okay?

[RaymondL]

Hi folks,

I have an RODI system (4 stage) and today using 2 separate TDS meters to measure the water being produced it reads at 1ppm TDS. Should I throw away the 5 gallons that I made, or is it nothing to worry about. I've always had 0 TDS, so I think it's time to change the DI filter.

Thankks

 

[Asm481]

Myself I would dump the five gallons and go with new di. No telling what that 1 ppm is.

 

[UnnamedReef]

Probably time to change the DI resin, but personally I've run into exactly the same question and used the water.

Like Asm481 said though, you don't ever REALLY know what the 1TDS is. Up to you, but I can say that I would and have used water like that while I waited for new DI resin with no adverse effects.

 

[JGT]

I go up to 5 then swap out. Have never seen any repurcussions.

 

[BryanM]

I like zero, but I don't think there's anything wrong with 1-2 either.

 

[Maize & Blue]

So 1-2 TDS is useable? I swap DI cartridges when it hits 1.

 

[reely989]

You’ll get a lot of different answers. It’s probably fine. Just depends on what’s in your water. There’s a guy here locally who has a great reef and runs straight tap water

 

[lombeard]

I recently ICP tested mine when it went to 1 as I was curious. You can see there results here: https://lab.faunamarin.de/en/share/analysis/osmosis/210052

Results will vary based on location but mine had some silicon and silicates show up when they were 0 before on 0 TDS.

 

[Randy Holmes-Farley Verified Community Expert]

If it was zero and is now 1, it is ok but will very soon rise more and it’s time to replace.

 

[Randy Holmes-Farley Verified Community Expert]

FWIW, I detail all about tds here:

What is TDS? by Randy Holmes-Farley - Reefkeeping.com