Soured saltwater?

[CK Amstutz]

I was told yesterday, by a man who has a stunning 185g, that any saltwater mixed up over two weeks sours. He told me to use it within the week I get it. Is this true? I get premixed reef water and usually change then and then within the next month. Now I am worried if I just need to buy when I am ready to do a water change.

 

[Spare time]

No its fine. Unless it was natural seawater, or has some organics in it, it won't "sour." Some salts with eleveated alkalinity and such will precipitate, but otherwise no you are fine. Some salts I wouldn't store would be reef crystals, coral pro, red box version of fritz's salt, etc..

 

[Dan_P]

I was told yesterday, by a man who has a stunning 185g, that any saltwater mixed up over two weeks sours. He told me to use it within the week I get it. Is this true? I get premixed reef water and usually change then and then within the next month. Now I am worried if I just need to buy when I am ready to do a water change.

Hey, could you ask him what “sour” means? How did he observe this souring? How was it measured?

 

[brandon429]

I have some scary practice in this. the man was right. it's variable home to home based on conditions, dilution etc but able to be replicated in small scale if wanted.

not that this eliminates all sourcing for souring but it's certainly repeatable 1000% for sure this almost killed my tank once.

skip to the save...leaving all stored water open capped, for evaporation, and just topping off 100% fixed all fouling. it's oxygen related, biotic, not chemical beyond rotting organisms in the water which are dealt with by keeping oxygenation. Motion isn't even required, my containers simply sit open topped. the water could easily go a month I've done it multiple times. my vase is one gallon, a change bottle is 5 it goes a month in between all fills the same mix of water. sometimes longer, never spoils.


it dawned on me that we maintain a biome in our water change containers. if you keep things capped, then these communities die off due to lack of 02 in about that much time dumping in old capped water was the #1 closest I ever came to killing my 16 year old reef vase. I poured the water in uncapped without smelling, it caused clouding, instant closing of corals, migration of all microbenthic animals like brittle stars out and up the top of the vase they literally crawled out.

now that I keep all storage containters of sw open capped, and top off before use, this has never happened again. the organic brown slicks at the bottom of the container are a mini biome. it's actually not a big deal to dry them/empty container and rehydrate...what's bad is capping off/no o2.

if you let your change buckets dry out and refill them, castings of previously anchored organisms get rehydrated and put back into suspension. you gotta breathe all that vs restrict it.

it smelled like doom rotten eggs when I sniffed the water. I knew at that point, about 2008 ish, to NEVER cap storage water we maintain the open biome.

to replicate in small scale, get two scummy water change 5 gallon containers that's been used a while. has real scum brown on the inside bottom, something that fizzes like nuclear uranium if peroxide is poured on it (compared to no action from a brand new bucket)

keep one capped off with new change water for one month.
keep the other open topped one month, rarely topped off.

smell the two at the end

 

[brandon429]

I 100% unequivocally have said always store change water uncapped and it stopped this risk in all pico reefs tested since. using other people's tanks to quad up your own experiment #'s helps in finding patterns, we literally tested thsi on thousands of small pico reefs easily wrecked by bad water.

I'm seeing a solid link to oxygenation fouling and not circulation-based fouling or settling of salts in any way. if change water sits in by blue container for 1 month open topped, uncirculated, when it's used nothing bad happens. ever.

 

[The0wn4g3]

This might be helpful...

How long can I store saltwater after mixing? | BRStv Investigates

For those reefers mixing small batches of saltwater and using it rather quickly after mixing, worrying about the Alkalinity and Calcium parameters shifting is typically not a concern. A growing number of reefers are mixing large batches of saltwater, less frequently and use

www.bulkreefsupply.com

 

[Randy Holmes-Farley]

I used my stored normal IO unstirred and unheated for about a month of automatic water changes, and I know of no chemical reason to be concerned about it, other than the potential for precipitation of calcium carbonate from all high alk mixes.

I would not store mixes with organics, such as Reef Crystals, since the vitamins may get metabolized by bacteria (no big concern, IMO), but if not stirred, it might become anaerobic for that reason.