Will Salt Water Go Stale?


Premium Member
I purchased 5 Gallons of salt water to do a water change with, then had to leave town before I had a chance to do the water change. When I get back it will have been a week. The water has sat in my garage in a sealed container. Is it usable still? Should I bother testing it first? Should I test for anything besides NH3, N02, NO3 or ph?

Is there a limit to how long you can store salt water mix?


New member
you may need to mix it some more to be sure the salt hasn't come out of suspension - test specific gravity. test for the standard 4 - nh3, no2, no3, ph and make sure they're in range. as long as it tests fine, you should be fine.
Where did it come from - a "live" system, the ocean, or did someone make it up from plain water and salt mix?

If there's nothing biologically active in it, it should be pretty much 100% stable as long as the temp and atmosphere aren't extreme. Aerate it a bit before you use it, by stirring or with an air pump.


Premium Member
The water came from my LFS, so its RO/DI already mixed with salt. I also by my RO/DI water for top offs there, since I don't have my own unit yet.