Distilled vreses RO water?
- Thread starter Davidb6
- Start date
I have used the "Culligan" machines at Wal Mart before with no problems. It's .33 a gallon here for refills if you bring your own container(s).
I normally take test strips and a dixie cup with me and check it before I actually fill the jugs that I way I don't have to worry about if the filters were actually changed or if they just checked it off on the maintenance card that's attached to the machine.
I normally take test strips and a dixie cup with me and check it before I actually fill the jugs that I way I don't have to worry about if the filters were actually changed or if they just checked it off on the maintenance card that's attached to the machine.
drummereef
Team RC
There's lots of people that used distilled. I would just test the TDS and make sure it's low. 
Distilled is fine. It is somewhat less pure than RO/DI but it is fine in a reef tank as long as it hasn't passed through a copper condenser; very rare today as EPA drinking water standards limit copper in drinking water.
mr_o98
Premium Member
I used to use distilled water for about 2.5 years before I bought an RO unit. I also know 2 other reefers that did the same. Distilled water is ususally run through some type of RO filtration. I bought an RO unit because I hated driving to the store buying enough water to fill a swimming pool and then carrying it home.
Usually RO is sold in those vending machines. It may not say RO but ofter it is RO with carbon and UV filtration. Having a TDS meter will tell you the true story as most RO water has a TDS of less than ten.
Never have quite understood that. I assume its based on the potential that water may contain chemicals that could evaporate along with the water and then be condensed again? If so then I suppose the quality of original water would dictate which filter mechanism is superior?
Watch it with Walmart...
Watch it with Walmart...
Just make sure you test any water you get from Walmart. I am currently completely redoing my tank because 5 gallons of walmart water had enough Ammonia in it after a Prime treatment to jump from .25ppm to 2.5ppm and cause a massive bacteria bloom and die off in my tank.
I know, that part is my own fault because I only checked the water before I primed it and not after but serious, RO drinking water with that much ammonia in it leaves me a bit suspect. Especially considering that I am not the first person locally to have this happen to.
Fortunately, I have 2 reefers within 20 miles of me that are willing to donate all the RO/DI I need for free if I transport it.
Watch it with Walmart...
Just make sure you test any water you get from Walmart. I am currently completely redoing my tank because 5 gallons of walmart water had enough Ammonia in it after a Prime treatment to jump from .25ppm to 2.5ppm and cause a massive bacteria bloom and die off in my tank.
I know, that part is my own fault because I only checked the water before I primed it and not after but serious, RO drinking water with that much ammonia in it leaves me a bit suspect. Especially considering that I am not the first person locally to have this happen to.
Fortunately, I have 2 reefers within 20 miles of me that are willing to donate all the RO/DI I need for free if I transport it.
Theoretically pure water has a specific resistance of 18.33 million ohms. RO/DI water can be in the neighborhood of 17.9-18.2 million ohms. Distilled only hits about 1-2 million ohms. That is still very good but not as pure as the DI filtered water. In some cases you may see triple distilled water from an all quartz still that can be close to 10 million ohms but it costs big $$$/gal. It is used in pharmacology where a pure water is needed that is also pathogen free. DI water is not pathogen free and would require post UV irradiation to be so. However, bacteria and viruses are not dissolved but suspended and don't decrease resistivity.
Thanks Tom
The distilled water vrs RO/DI arguement seems to come up on a regular basis. Like many RC disputes seems like argueing over how many angels can fit on a pin head. I suppose I may have to upgrade my $20 TDS meter ... battery apparently isn't powerful enough to measure millions of OHMS and zero is so confusing
The distilled water vrs RO/DI arguement seems to come up on a regular basis. Like many RC disputes seems like argueing over how many angels can fit on a pin head. I suppose I may have to upgrade my $20 TDS meter ... battery apparently isn't powerful enough to measure millions of OHMS and zero is so confusing
Kevin,
That is mainly based on the cell constant of the meter as to how high the meter can read. Many meters also may read in microsiemens µS/cm<sup>2</sup> which is the reciprocal of the ohms/cm<sup>2</sup> (18,330,000 ohms = 0.055µS). Lab type meter use cell constants in the 0.1-0.05 range for measuring ultra pure water. You really don't need that fine a reading as a TDS of 1 is = to about ~1.8 µS.
That is mainly based on the cell constant of the meter as to how high the meter can read. Many meters also may read in microsiemens µS/cm<sup>2</sup> which is the reciprocal of the ohms/cm<sup>2</sup> (18,330,000 ohms = 0.055µS). Lab type meter use cell constants in the 0.1-0.05 range for measuring ultra pure water. You really don't need that fine a reading as a TDS of 1 is = to about ~1.8 µS.
