I've seen reports on how bottled water often has bacteria (the kind you buy for drinking water). It sits in the shelf for too long and can go bad. The bacteria may or may-not be harmful.
Saltwater in a "less than steril" container will also start coloniazing bacteria over a period of time. The question at hand is..... is it a good bacteria....or bad.
If the water appears to be a bit cloudy...then there is way too much bacteria in it to use in your saltwater tank (I doubt if its cloudy). If it has an smell to it....same conclusion.
If it was stored in a plastic container that is of pooy quality, well then over a long period of time it may be possible that chemicals used to make the plastic could leach into the water since salt is more curosive than plain water. (or chemical reaction). What was originally in that container?
So.....
If the water's gonna` stink....pour it down the sink.
But... if your dead set on using that water... just use alittle at a time by mixing it with new water. There is prob a 1 in 1000 chance that there is anything wrong with it. IMO
Food for thought...........?? {please excuse all spelling errors}
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