RO water TDS

[ItouchedThebutt]

Just bought a TDS meter for my RO water, I buy my from a LFS. Tested it and came out at 2ppm TDS, is that okay or ideal? The back says 0-50 says that's RO water levels as well as distilled water.

 

[dwest]

Just bought a TDS meter for my RO water, I buy my from a LFS. Tested it and came out at 2ppm TDS, is that okay or ideal? The back says 0-50 says that's RO water levels as well as distilled water.

If it’s ro water, 2 is ok. If it’s rodi the reading should be zero.

 

[Hitman]

I personally wouldn’t put anything but zero tds in my tank unless it was a emergency. You never know what that 2 TDS is or how toxic it could possibly be in the long run. Just my two cents.

 

[sghera64]

Zero TDS water can become 4+ TDS water simply by being exposed to air as it will pick up CO2 and dissociate forming ions which are measured by the meter. That CO2 (and bicarbonate) are harmless to our reefs.

 

[ItouchedThebutt]

Zero TDS water can become 4+ TDS water simply by being exposed to air as it will pick up CO2 and dissociate forming ions which are measured by the meter. That CO2 (and bicarbonate) are harmless to our reefs.

That kinda makes me feel like that's what it is, I did not test all my jugs but I tested my ATO to see how it works and I leave the lid off on it so when it draws water it doesnt crush the jug. So that's exposed to air.

 

[ItouchedThebutt]

My friends TDS from another LFS is 14-16.. that bad?

 

[pdxmonkeyboy]

That 2ppm could be liquid death!! Exposing it to air will make the liquid death mulitply and now you are essentally pouring diesel in your tank.

seriously dude, 2ppm is absolutely fine. that is parts per million!

 

[ItouchedThebutt]

That 2ppm could be liquid death!! Exposing it to air will make the liquid death mulitply and now you are essentally pouring diesel in your tank.

seriously dude, 2ppm is absolutely fine. that is parts per million!

Im sorry is there first part sarcasm..? Lol

 

[NY_Caveman]

If you get RO/DI from the LFS in a dedicated jug and take it home TDS will never measure 0. Exposure to air and the jug will cause it to rise. However, that exposure is okay. TDS is a general measure of all solids and it is likely what it is exposed to in these cases is not toxic. So that TDS of 2 for example is likely not copper or arsenic.

 

[pdxmonkeyboy]

could that 2ppm be diesel??

 

[NY_Caveman]

My friends TDS from another LFS is 14-16.. that bad?

When I bought from the LFS it was usually 7-14 when I tested in the car. If concerned bring your TDS meter and ask them to test it before it hits your jug.

Also, their reservoir may be low or their maintenance poor. Or they need to replace membranes, etc. as mentioned above.

If interested I had this thread going a while back.

Poll: Do You Know Your TDS?

 

[ItouchedThebutt]

I have dedicated jugs for it. Should you clean your RO jugs at all? What levels of TDS should you be concerned of?

 

[Hitman]

I wash mine out with vinegar and rodi water every other month.

 

[ItouchedThebutt]

I would love to see a poll in how much vinegar refers go through seeing that's the go to cleaner lol

 

[Hitman]

2 gallons a month for me. I’ll say I probably use more then I should tho lol

 

[ItouchedThebutt]

Do you use any kind in particular?

 

[Hitman]

The cheapest distilled white vinegar I can find. Usually Walmart brand is the cheapest.

 

[pdxmonkeyboy]

The cheapest distilled white vinegar I can find. Usually Walmart brand is the cheapest.

you shop at Walmart?? gross

 

[Laith]

I test the TDS of the water coming out of my RO/DI unit. If it shows anything but zero I change the DI resin... much easier than wondering what aTDS reading of 1 or 2 is actually made up of!

And yes, any RO/DI water in a container will slowly show a TDS over zero. As mentioned, this is normal. Hence why I measure TDS of the water as it exits the RO/DI unit.

 

[Randy Holmes-Farley Verified Community Expert]

You can possibly get 1-2 ppm from totally pure water just from CO2 in the air mixing into it.