Do Salt Mixes get old? 20 years?

[JMetaxas]

I have about 8 cases (50 gal x 3) of Instant Ocean salt that I've kept in my garage for about the last 15-20 years. Times flies when you have kids, raise them, etc etc.....

Some of the salt has gotten hard in the bag, some not.

Is there anything that would cause the salt to go "bad'? Could there be insoluble formed that wont go into solution causing perhaps low Alkalinity or calcium?

 

[hijinks7]

https://www.bulkreefsupply.com/video/view/faq-41-does-aquarium-salt-ever-go-bad/

 

[Randy Holmes-Farley Verified Community Expert]

Precipitation of calcium carbonate is the primary thing that goes wrong in a mix like normal IO that does not contain organic matter (its a different story for those that do, and the BRS video seems to not account for that). If the alkalinity is normal once any solids have settled, the mix is OK.

IO normally has a pretty high alk and lowish calcium. So bear in mind that is alk drops back to, say 7 dKH, that calcium has also declined and is likely lower than you'd prefer.

 

[Tobbe]

I had some hw reefer marine mix there was some hard clumps in it i smashed it with a rubber mallet and mixed and measure it and it was same

just break it up so the salt is even in bucket

 

[Skynyrd Fish]

If you try it id mix the entire bag of salt at once.

 

[JMetaxas]

I mixed up a bag of IO a few weeks ago and got an Alkalinity of 3.5 dkh and Calcium of 350. Both quite low. Test kits are Red Sea brand new. This is what got me thinking about 20 year old salt mix.

I've since slowly raised the Alkalinity using BRS two part to 7,5 dkh.