It won't "go bad" - I try to keep 10 gal tank full and on hand at all times. All I do is keep a spare heater (not entirely neccessary in a heated room but...) and a small pump aimed at the surface. this makes quick work of water changes for my smaller tanks and if I'm planning a change on my bigger tank I'll set up another 10 a few days ahead of the weekend. Question though... where are you getting it from??? I'm assuming from a LFS supply of mixed water. A 10 gal tank costs nothing and having a bag of salt mix laying around would be more convienent then fetching a pail of water wouldn't it???
I get it from our saltwater fish store it cost about 30 cents a gallon and i only need a gallon and its on my way home. Thanks for the info.but does it need to have flow to stay good?
I see,
not flow - air exchange - its complicated chemistry but basically you have to keep the o2/co2 in balance or the pH, and alk will get out of wack - an airstone would do the same thing for you if thats easier???