Tap Water TDS is 1

[baseballfanatic2]

My tap water TDS is showing 1. Do I still need to run it through rodi unit? Or can I just do salt mixes with this water? My until seems to mess with my sink plumbing causing leaks. So don't want to risk it.

 

[Phil D.]

ALWAYS RO/DI, because you don't know what else is in it. You can get a quick disconnect to put on the faucet, (like the old time dishwasher connections), to hook it up and unhook it.

 

[Keesers]

I would absolutely still run the RODI just as Phil said you don’t know what is in the water still. That number is just giving you an idea of total dissolved solids and works very well for that but unless you are testing for everything there is no way to know. What if there is phosphates, chlorine, chloramines, and ammonia but just at small numbers they start to add up quick in a closed system like you tank. IE: I have to run double carbon blocks double di resins on my RODI and a gfo container to get everything out of my water here and that only gets me less then 100 gallons. On one carbon and and one di that’s why I run double so if the first one fails I’ve got second then get the filters live in middle of orchard so possible has something to do with my water. Hopes that’s helps we want to give our tanks and animals best water we can in my opinion

Here is so info I found
“TDS in drinking-water originate from natural sources, sewage, urban run-off, industrial wastewater, and chemicals used in the water treatment process, and the nature of the piping or hardware used to convey the water, i.e., the plumbing. In the United States, elevated TDS has been due to natural environmental features such as mineral springs, carbonate deposits, salt deposits, and sea water intrusion, but other sources may include: salts used for road de-icing, anti-skid materials, drinking water treatment chemicals, stormwater, and agricultural runoff, and point/non-point wastewater discharges.

In general, the total dissolved solids concentration is the sum of the cations (positively charged) and anions (negatively charged) ions in the water. Therefore, the total dissolved solids test provides a qualitative measure of the amount of dissolved ions but does not tell us the nature or ion relationships. In addition, the test does not provide us insight into the specific water quality issues, such as Elevated Hardness, Salty Taste, or Corrosiveness. Therefore, the total dissolved solids test is used as an indicator test to determine the general quality of the water. The sources of total dissolved solids can include all of the dissolved cations and anions.

 

[Brett S]

It would probably still be a good idea to filter it, but with a source water TDS of 1 you can just go with DI only. The RO membrane in an RODI filter is used to remove the majority of the junk from the water because the DI resin is expensive, but for most people even after the RO membrane the TDS is still 5 or 7, so you’re already in better shape than that.

One advantage of going DI only is that it can be faster than RO so it’s more feasible to connect it temporarily if you only need to make small quantities of water.

 

[samnaz]

No, you don’t ‘need’ to run it through an RODI unit. I used tap water with 250+ TDS for three years without issue, still do, but most certainly the majority of reef keepers use RODI and sware by it.

If it were me I’d try the tap water out and see what happens. But your system may vary greatly from mine which is just a simple nano invert-only mixed reef.

 

[Mortie31]

I would check if your in an area that uses chloramine in its water, if so use a specific prefilter for this as the standard ones don’t filter it out, other than that I wouldn’t worry about it.. wish I had tap water that clean it would make life so much easier than the 350 TDS I have!!

 

[Mortie31]

What if there is phosphates, chlorine, chloramines, and ammonia

You have to buy a specific chloramine prefilter cartridge to remove that, ammonia and phosphates are really easy to measure. With your home test kits. You are correct in quoting what TDS measures but with a measurement of 1 I wouldn’t be worried, after all most of us use cheap hobby grade TDS meters and they can be so inaccurate.

 

[jrill]

Get it tested then decide

 

[mfinn]

First thing I would do is, do a test with a different TDS meter to see if it backs up the first TDS meter.

Second thing is, I would try and get a water report from the whatever agency in your area has control of water testing.
Figure out exactly what that low number is.

Tap water in my area tested in the 15 to 20 TDS for decades and I used it for my softy reefs with no real issues.

 

[Opus]

A normal carbon block filter will break down chloramines, maybe not as well as one made specifically for them but they will work.

OP, I would do as mfinn suggested. Make sure the 1 tds is accurate and see if you can get a water report for your water district. If this is well water then you could have another set of issues. If 1 tds is accurate then I would just use a carbon filter then DI filter. You should be able to get around 4000 gallons of 0 tds water from a DI cartridge.

 

[Multra]

I would get another TDS meter. Highly doubt it is possible to have 1 TDS tap water.

 

[Justin Cook]

I would get another TDS meter. Highly doubt it is possible to have 1 TDS tap water.

That was my first thought but I suppose it could be. I thought my tap TDS was low at 37 ppm! I still run it through carbon and DI resin but that's just me. With a TDS of 1, it might take a while to exhaust the DI resin and therefore keep the cost down quite a bit. If you can find a water report from your county or city (whichever provides the water) you can see if you are dealing with chloramines. If you do have chloramines, the "Total Chlorine" and "Free Chlorine" numbers won't quite match. I mention chloramines because I ended up using a carbon block specifically for them in my system. It's a new thing for my county and the standard carbon block wasn't cutting it.

 

[Pntbll687]

I agree with double checking the TDS to make sure it is actually 1.

If it is 1, I would just run it through carbon block and then DI.

Is this well water or city water?

 

[Tiger Brown]

I also agree with mfinn on this. Your municipal water authority can give you a report on exactly what is in your tap water based on their testing (I do understand this could vary slightly based on the pipes it travels to your home).

I also like that there are reefers that actually do use tap water without an RO/DI. I am a purist in philosophy and think that filtering is the best way to go about it, but I run my FOWLRI (I include the I for invertebrates, no coral though) with tap water treated with nothing but marine stress coat added. As mfinn said, it can be done successfully, but with caution.

 

[Mortie31]

A normal carbon block filter will break down chloramines, maybe not as well as one made specifically for them but they will work.

Normal carbon blocks don’t remove all chloramine, and I don’t want any getting through... it’s a pretty nasty chemical, I would advise anyone who’s water company uses it to have a proper chloramine filter..

 

[NoLarvatusplease]

My tap water TDS is showing 1. Do I still need to run it through rodi unit? Or can I just do salt mixes with this water? My until seems to mess with my sink plumbing causing leaks. So don't want to risk it.

Just curious where you live where tap is only 1tds.?

 

[Randy Holmes-Farley Verified Community Expert]

Just curious where you live where tap is only 1tds.?

The op has not been on in a while, and I personally expect that value was likely a testing issue.