Does mixed SW go bad?

[NewB]

I premix my SW and store it in a trash can I bought. When I do my weekly water changes I always have some left. Is there a chance of this water turning bad? Should I occasionally empty the container and rinse it out?

I ask because I thought I smelled a moldy smell when I did my last water change.

[captexas]

Did you have the water constantly mixing the whole time? You don't want it to just sit for very long as stuff will settle out of the mixed solution. I always kept a mag 5 running in my mixing tank otherwise it would smell and look nasty after sitting for a few days.

[NewB]

Yeah, I have the a powerhead in there keeping the water circulated. It doesn't look bad. Just seemed like a faint moldy smell to it.

[matt]

Make sure you don't lean over it munching on a tuna sandwich and should be okay :D

[GaryP]

There may be some chemical changes to the water. For example, calcium may precipitate and alkalinity may be depleted by CO2 being absorbed. If you only have a small percentage of old water mized with new water, or you pump up the levels with additives its probably OK.

[Flobex]

i dont think it shoould go bad... you have mixed SW in your tank that is just fine...