Storing ASW

[delandreefer]

I was wondering how long everyone is comfortable keeping their saltwater after mixing. I mix a 30 gallon container and try to use it all within two weeks. I keep a pump in it to keep it flowing. Is there any reason not to store it?

 

[Randy Holmes-Farley Verified Community Expert]

Assuming it does not have organics in it (a few like Reef Crystals and Tropic Marin Bioactif do), then it can be stored a long time unstirred and unheated. I store mine for more than a month. Organics in the mix can degrade and potentially grow bacteria.

Some mixes with high alk and pH may suffer precipitation of some calcium carbonate on heaters or pumps if you keep them going, but in general it won't typically drive levels excessively low (but alk may be detectably lower than when first made). A lot of folks might actually prefer the lower alk, and some people add acid to achieve that. The calcium drop will be minimal.

 

[redfishbluefish]

I don't use it and don't know why, but Red Sea Pro states to use their mixed saltwater within 4 hours.

 

[Randy Holmes-Farley Verified Community Expert]

I don't use it and don't know why, but Red Sea Pro states to use their mixed saltwater within 4 hours.

They are trying to reduce precipitation of calcium carbonate:

 

[Blue Lip]

wow! Thanks Randy.

 

[Randy Holmes-Farley Verified Community Expert]

wow! Thanks Randy.

You're welcome.

Happy Reefing.

 

[melev]

I mix up 250g of saltwater at a time, and this usually lasts me about three months. I keep it in a sealed container with a circulation pump to keep it moving all the time. This has worked well for me for the past four years.

 

[Jlobes]

I mix up 250g of saltwater at a time, and this usually lasts me about three months. I keep it in a sealed container with a circulation pump to keep it moving all the time. This has worked well for me for the past four years.

wow, really? three months. I guess whatever works for ya, but seems excessive. what brand of salt?

 

[Duke4Life]

This is good to know as I have 20g I picked up 2 weeks ago and haven't used. Was about to pour it out.

 

[melev]

wow, really? three months. I guess whatever works for ya, but seems excessive. what brand of salt?

I change 55g of water at a time, so it takes a while to deplete my reserve. Salts I've used with this method: Sybon Reef, Fritz and now Salinity.