Reverse Osmosis or steam distilled H2O?

[Heliox]

I have been using steam distilled water from my local pharmacies for the past few years. But everyone seems to extol the virtues of reverse osmosis water.

I did not think I could find any bottled reverse osmosis water, but have now realized that we fill our water cooler bottles with water that is RO. And along with being RO the dispenser claims to have ultraviolet sterilization and mechanical filtration.

This is from a large chain grocery store here in Vancouver.
I can find no information from the company about any constituents that might be in the H20.

Is it safe to use this RO water??
Should I test the water for anything before using.

I live in a rental unit and can not install a unit here to produce my own RO water.


Interestingly, my LFS and a few other aquarists I have met at the store all use the tap water with conditioner, and all claim success here with Vancouver water.

 

[lcstorc]

The quality of the RO water depends largely on the membranes. If they are replaced appropriately then the water would be fine. The best way to tell is with a TDS meter which will tell you the Total Disolved Solids.
It is certainly possible to keep a tank with tap water. The reason we avoid it is the additional contaminents which feed unwanted algae growth.
The lower the TDS reading the cleaner the water. A properly maintained RO system will have a TDS <10. RO/DI is usually 0-1.

 

[Heliox]

Hmm, I guess then I best stick with my distilled water until I can find someway of measuring the TDS or finding a source of information about their water.

Thank you very much Lynn, much appreciated.

 

[burning2nd]

just buy a RODI system..

The Filter Guys

 

[DaveK]

I have been using steam distilled water from my local pharmacies ...

Keep in mind that it is possible to have problems with this water also. Most likely you are ok, but if the water was distilled and there was copper used in the boiler or condenser or copper pipe used, you could have a problem with copper in the water.

 

[lcstorc]

TDS metere are relatively cheap and easy to use.
Having your own RO/DI is certainly easier and more cost effective but a meter is a good option as well. Most people buy a TDS meter to check their RO/DI to know when they need to change the membranes.