Saltwater expiration?

mrs.nanoreef · Mar 5, 2014

So I have heard that if you mix up saltwater, that it goes bad after a week.... what is the explanation on this? Does it go bad? Are their things to keep it from turning? How long exactly do you have to use it? And is this true? And why? Also, a little bit about my mixing set up, I have a 2.5 gallon jug with a powerhead in it to keep things mixed up that I keep on till I use the water and the cap I set back on it without screwing it on cuz of the powerhead cord, but have noticed no or very little evaporation. Thank you for reading.

HoaglandDiver · Mar 5, 2014

tagging along... but I recall someone stating similar -- over time, it can degrade.. not sure how true.. will be interested to see what people post.

mrs.nanoreef · Mar 5, 2014

I get that if there is evaporation happening cuz the elements will evaporate out but if there is little to none I wonder if it's true and for how long can it be "good" still.. I've heard several lengths. So yeah I'd like to know the real answer.

Eric B · Mar 5, 2014

Well this is my opinion on that subject as I have used saltwater that was mixed and in a barrel many weeks later I just make sure and mix it really well for a few hours and test it before I use it (I check salinity, CA, Mag & Alk and adjust it as needed). The way I look at it we have salt water in our tanks and some people change water once a month and some longer than that and everything in the tank is perfectly fine with tank inhabitants! I seriously doubt it degrades sitting mixed in a closed barrel versus my open top tank and sump but I would at the least mix it for a few hours and adjust salinity before I use it.

Bad Company · Mar 5, 2014

When water sits and evaporates, only H2O evaporates out. All minerals are left behind. The only other things that will leave the water are volitiles like alcohol etc. Chemically it should be fine to let your salt water sit, especially in a clean bin without nutrients.

SloppyJ · Mar 5, 2014

I'm not sure that salt water "expiring" is true. What about the salt water in your tank. They only thing that should be done is aeration to increase DO if it's just been sitting. Other than that, I see no reason why it would go "bad".