What is an acceptable TDS value?

[RaymondL]

I'm wondering if I have a reading of 1 for TDS does this mean that I really should be swapping out my Sediment membrane, or something else?

 

[KStatefan]

I change my DI resin to maintain 0 tds.

 

[Uncle99]

I'm wondering if I have a reading of 1 for TDS does this mean that I really should be swapping out my Sediment membrane, or something else?

I do nothing till 5ppm.
At 5 I change resin.
More than 10, I check membrane.
Sediment and Carbon every 6 months cause they are cheap.
Mostly I get 0TDS, sometimes 1, but if I swirl the probe, I get 0.
I can see the sediment filter needs change when it turns beige from white.
New Carbon always a good thing.

 

[Miami Reef]

Trace TDS is handled with the DI resin. If you see 1ppm, it’s likely the DI is exhausted.

I change my sediment when it looks dirty to my eyes.

 

[jimk60]

One or two TDS for me isn't a problem. It does mean that it's time to order and change the DI resin. This is assuming your using resin.

 

[Zach B]

As others have stated, I also maintain my rodi to keep it at 0. I think it's our best chance of keeping the best water possible

 

[RaymondL]

Thank you all! I was mistaken - always thought that TDS value is dependent on the sediment cartridge only.

Cheers

 

[vetteguy53081]

I'm wondering if I have a reading of 1 for TDS does this mean that I really should be swapping out my Sediment membrane, or something else?

Once I approach 5- time for a change

 

[DanyL]

I think it's best if everyone would also mention what types of corals they keep, because not all are as sensitive to "unknown" elements as others.
Which points me to the next point - TDS is essentially measuring "unknown" dissolved elements, it does not say what it is, which like I mentioned before could be a problem for some corals if said "unknown" is for example copper, aluminium, etc.

So for me, SPS dominant mixed reef I always keep TDS 0, and change resin once it gets to 1.
That being said, I also don't hesitate to use TDS 1 for a few liters (5-10 liters == 1-2.5 gal) if I really need to and don't have the time at that moment to replace it, but I'll also not wait for too long with it either.

And as others mentioned here - trace TDS is handled by DI resin.
But I also highly recommend getting inline sensors to measure TDS in 3 spots: Input, before resin and output.
This allows you to measure the differences between each step and ***** what filter was depleted and needs a replacement.

EDIT: lol what a typo haha assess*

 

[Miami Reef]

TDS is essentially measuring "unknown" dissolved elements, it does not say what it is, which like I mentioned before could be a problem for some corals if said "unknown" is for example copper, aluminium, etc.

Agreed.

 

[ekandler]

Anything over 0.

 

[bnord]

for me it has to do with your source. I have a well and have tested ICP on tap water, RODI with a 5 TDS and the same system with freshly changed resin running 0.

The Tap water is pretty scary, and the two RODI are indistinguishable on ICP

I too change on resin color shift, or if it creeps above 4.