Reef nutrition

Should Neptune's 2 TDS water worry me?

Hi all, I had my buddy grab a 200G water card at Neptune for his first reef build. I'm a noob when it comes to RODI but I know Sunnyvale uses chloramines and is in the 300-400 TDS range so I plan to pickup a BRS 7 stage system in a few months.

The employee at Neptune checked their TDS meter for me and said it was running at 2 TDS. BRS says that any TDS is bad because it is pollutants breaking through.

Should we discontinue using Neptune's water? Or is it nothing to worry about?
 
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I have no experience with Neptune’s water. But I wouldn’t use or trust any supposedly RODI water that has 2 TDS unless they also have some rock-solid explanation. Even then I wouldn’t use it.

It’s not that 2 TDS is inherently bad. It could be just sodium chloride, in which case that amount is completely insignificant. The point is that it means something unknown is in water that isn’t supposed to have anything in it, which is suspect.
 
I have no experience with Neptune’s water. But I wouldn’t use or trust any supposedly RODI water that has 2 TDS unless they also have some rock-solid explanation. Even then I wouldn’t use it.

It’s not that 2 TDS is inherently bad. It could be just sodium chloride, in which case that amount is completely insignificant. The point is that it means something unknown is in water that isn’t supposed to have anything in it, which is suspect.
I only have a TDS meter from my ZeroWater home water pitcher so I doubt I could test it accurately. I'm just going off of their in-line meter. Their explanation was "we use it on all our tanks and our fish and corals are fine. Look around you".
Thank you for bolstering my suspicions.

Isn't Neptune a BAR Sponsor? Could they explain?
 
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I’m not 100% sure. But I remember a long time ago. Someone told me that it comes out zero but if it sits it goes up a little. Cuz water collects stuff. A quick google search would probably be best.
 
2 is perfectly fine. At the filling station, you can expect to see upward of 5-10. So, 2 is very good.

My RO water runs through an industrial DI tank with a scientific grade TDS sensor as a monitor. That sensor will detect any TDS impurities a week even before the best hobby grade TDS will read 1. That means any TDS impurities that is measurable by the time you purchase the water may simply be picked up from the 200ft of PVC pipe that transfers the water from my main collection tank to the tank in the ramp area, not from the source water.

BTW…back in the days before the popularity and availability of DI resin, even 100 TDS was considered “good”! San Jose tap water averages about 300-500 straight out of the tap depending on the time of year. So relatively speaking, 2 is actually pretty good. Also don’t forget to allow for margin of error of the measuring device. They have all have their built-in margin of error.
 
Hopefully not a thread hijack, but I'm a little confused by how San Jose water has a tds of 300. I'm in Redwood City, and I've tested the water from my tap to be about 30 TDS. I actually tested my tap with a 5ish different TDS meters to verify that, including a bluelab guardian meter ($400, which doesn't mean it's actually good, but I got access to it). My RO comes out at around 2. DI 0 (obviously).

Are we talking different units somehow, is San Jose water messed with, or did I somehow misread all these meters?
 
Hopefully not a thread hijack, but I'm a little confused by how San Jose water has a tds of 300. I'm in Redwood City, and I've tested the water from my tap to be about 30 TDS. I actually tested my tap with a 5ish different TDS meters to verify that, including a bluelab guardian meter ($400, which doesn't mean it's actually good, but I got access to it). My RO comes out at around 2. DI 0 (obviously).

Are we talking different units somehow, is San Jose water messed with, or did I somehow misread all these meters?
I have 450 out of my tap downtown San Jose with new copper pipes. Lots of different counties in the bay get their water from different sources.
 
I have 450 out of my tap downtown San Jose with new copper pipes. Lots of different counties in the bay get their water from different sources.
Correct. Like everything other commodities, water is sometime sold to different areas by different companies that share the same common piping system. In San Jose for example, sometime we get our water from Hetch Hetchy, San Luis, and other places as well.
 
I only have a TDS meter from my ZeroWater home water pitcher so I doubt I could test it accurately. I'm just going off of their in-line meter. Their explanation was "we use it on all our tanks and our fish and corals are fine. Look around you".
Thank you for bolstering my suspicions.

Isn't Neptune a BAR Sponsor? Could they explain?

BTW..I am not a BAR sponsor. Not officially. I am just here but the shop does give complimentary discount to BAR members anyway, if you ask for it.
 
When I lived in south San Jose we were on well water. We had no chloramines but fairly high tds because of sediment. The sediment got taken care of by the pre filter pretty easily and the rodi took care of the rest.

@JVU’s point is valid in that you simply don’t know what the 2 TDS is. It could be something benign like salt (like previously mentioned) or it could be copper. The TDS meter can’t tell the difference. I think the evidence that it is the same water they use to fill their own tanks and they are doing fine isn’t conclusive to say one way or the other but it definitely bolsters their claim that it’s fine.

Like others, I normally didn’t change out my DI until I hit 5. To each their own though.
 
Hopefully not a thread hijack, but I'm a little confused by how San Jose water has a tds of 300. I'm in Redwood City, and I've tested the water from my tap to be about 30 TDS. I actually tested my tap with a 5ish different TDS meters to verify that, including a bluelab guardian meter ($400, which doesn't mean it's actually good, but I got access to it). My RO comes out at around 2. DI 0 (obviously).

Are we talking different units somehow, is San Jose water messed with, or did I somehow misread all these meters?
I vouch for the 300 tds from tap :)
 
Hopefully not a thread hijack, but I'm a little confused by how San Jose water has a tds of 300. I'm in Redwood City, and I've tested the water from my tap to be about 30 TDS. I actually tested my tap with a 5ish different TDS meters to verify that, including a bluelab guardian meter ($400, which doesn't mean it's actually good, but I got access to it). My RO comes out at around 2. DI 0 (obviously).

Are we talking different units somehow, is San Jose water messed with, or did I somehow misread all these meters?
The water in Campbell (still SJ) comes out of the tap at ~200-250, depending on time of year. The water up in Berkeley has a lower value, at ~30 or so TDS out of the tap instead, and I know someone that actually has used it before for years to mix and use in their tanks.

If you check out the water at some water fill stations, which uses some pretty high end equipment, it comes out at 1-2 TDS, which I've used before in the past, with no issues.
 
What’s a good trustworthy TDS meter that doesn’t break the bank?
On Amazon there's a billion of them for $10-$20. I bought a couple, tested a couple samples, and then returned all but the one that seemed accurate. My testing samples were some RO, some RODI, some distilled, tap, and some RODI with varying bits of salt in it.

I was just looking for one that consistently reported 0 for the distilled water, and oversee increased when I threw some salt in the water. I figured all the really matters is it registers 0 when it should, and non zero when it should. Knowing if it's 2 vs 3 TDS seemed to me not super actionable. I'll just use it to change filters when I see it creep up, along with seeing if my DI resin changed color.

And fwiw, the super expensive one I bought, thinking it'd be the most precise, was one of the least informative ones. It only measured in increments of 5. I ended up keeping one that cost about $12 and came with a pH meter too (though I never tried to pH meter and online reports they're garbage).

Edit: I also debated if it was moral to buy multiple knowing I'd only keep one. I normally wouldn't do that, but here if they're not giving me a correct number they're literally not working properly, so it seemed appropriate.
 
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