Looking for a reef chemist here

[SaltwaterGuruNeeded]

I'm just curious about sea salt. I'd like to know more in depth of why it's not good to use sea salt that has moisture in it to use it in a fish tank. I'm a little confused because it gets wet/ dissolved into our aquariums and I'm pretty sure alot of salt on the market comes right out of a wet environment like the sea. Infact almost all salt comes from the sea/ a body of water. Just would like to know what reactions happen that make the salt unsuitable for an aquarium once damp or exposed to moisture. What could I do to fix it or substitute what was reacted, if there's a way. Again just curious of the science behind it.

 

[Righteous]

Where have you heard that? I’ve never heard that it’s unsafe.

If your salt gets moisture in it, it’s going to end up clumping together and possibly precipitating out some stuff. If you’re using only some of the salt at a time you may end up with the various constituents out of balance based on it separating and being hard to mix. But if your using the whole bucket/bag then I don’t see an issue as long as you mix it thoroughly.

Also I don’t think anyone wants to pay for the weight of the water in wet salt mixes.

 

[Dolphins18]

I'm just curious about sea salt. I'd like to know more in depth of why it's not good to use sea salt that has moisture in it to use it in a fish tank. I'm a little confused because it gets wet/ dissolved into our aquariums and I'm pretty sure alot of salt on the market comes right out of a wet environment like the sea. Infact almost all salt comes from the sea/ a body of water. Just would like to know what reactions happen that make the salt unsuitable for an aquarium once damp or exposed to moisture. What could I do to fix it or substitute what was reacted, if there's a way. Again just curious of the science behind it.

I am no chemist but I used salt for many years that would always get moisture in it and clump into huge blocks, not once did I throw any out. I mean I used it for probably 15 years like this to be honest.
I don't typically love red sea products, but I switched to their coral pro sea salt not long ago, and it never clumps. I've actually been wondering about how it never gets clumped when moisture gets in, but it doesn't. Anyway, I wouldn't stress, unless it got like a half a gallon dumped into it, but even then I might use it personally lol.

 

[Randy Holmes-Farley Verified Community Expert]

All sea salt mixes contain moisture.

But too much moisture will dissolve the salt in small places on the surfaces of salt grains (causes clumping, but that's not the main concern), and allow calcium and carbonate to come together in super high concentrations, precipitating calcium and magnesium carbonate, and maybe other things.

They will not redissolve, and are lost.

In more water, the idea is to dissolve and separate then from one another before they precipitate.

 

[SaltwaterGuruNeeded]

All sea salt mixes contain moisture.

But too much moisture will dissolve the salt in small places on the surfaces of salt grains (causes clumping, but that's not the main concern), and allow calcium and carbonate to come together in super high concentrations, precipitating calcium and magnesium carbonate, and maybe other things.

They will not redissolve, and are lost.

In more water, the idea is to dissolve and separate then from one another before they precipitate.

Thanks, interesting.

 

[Righteous]

But too much moisture will dissolve the salt in small places on the surfaces of salt grains (causes clumping, but that's not the main concern), and allow calcium and carbonate to come together in super high concentrations, precipitating calcium and magnesium carbonate, and maybe other things.

Does this happen appreciably in moist air, or does it need a fair amount of water… i.e. how airtight should we keep open salt?

 

[Randy Holmes-Farley Verified Community Expert]

Does this happen appreciably in moist air, or does it need a fair amount of water… i.e. how airtight should we keep open salt?

If you live in Phoenix, it may not matter, but elsewhere the humidity will get in fairly quick to an open container. Hermetic sealing isn't necessary, but a decent lid is good.

Years ago, when I lived in North Carolina, I noticed water drops on the hardwood floor of a dining room that we hadn't used for a long time. Since there were no water pipes above it, I was at a loss to figure it out, until I realized it was spilled table salt that had dissolved into the high humidity air and made little puddles on the floor.

 

[SaltwaterGuruNeeded]

All sea salt mixes contain moisture.

But too much moisture will dissolve the salt in small places on the surfaces of salt grains (causes clumping, but that's not the main concern), and allow calcium and carbonate to come together in super high concentrations, precipitating calcium and magnesium carbonate, and maybe other things.

They will not redissolve, and are lost.

In more water, the idea is to dissolve and separate then from one another before they precipitate.

So clumped salt may still be good? I tossed out a 5 gal bucket of salt because it was a solid block. Was opened and then closed for about 4 years.

 

[Randy Holmes-Farley Verified Community Expert]

So clumped salt may still be good?

Yes, if you can dissolve it and the alk, once settled and clear, is normal, the salt is OK to use.

 

[SaltwaterGuruNeeded]

Yes, if you can dissolve it and the alk, once settled and clear, is normal, the salt is OK to use.

Hmm...Good to know.

 

[SaltwaterGuruNeeded]

Yes, if you can dissolve it and the alk, once settled and clear, is normal, the salt is OK to use.

So what is the main concern with old salt, ik salt itself doesn't expire, but I mean salt mix. Is it the alk?

 

[Randy Holmes-Farley Verified Community Expert]

So what is the main concern with old salt, ik salt itself doesn't expire, but I mean salt mix. Is it the alk?

It is that if alk is low, calcium and/or magnesium carbonate has precipitated and will not redissolve. That precipitate may also take down certain trace elements with it.

 

[SaltwaterGuruNeeded]

It is that if alk is low, calcium and/or magnesium carbonate has precipitated and will not redissolve. That precipitate may also take down certain trace elements with it.

Lol, it's complicated isn't it. So if alk is low when I mix a batch, don't use it?

 

[Randy Holmes-Farley Verified Community Expert]

Lol, it's complicated isn't it. So if alk is low when I mix a batch, don't use it?

Chemistry usually is when you look deep enough.

 

[SaltwaterGuruNeeded]

Chemistry usually is when you look deep enough.

Sorry to nag you but, would you know how much water impurity or percentage of water is in the instant ocean salt mixes, it's for a salt calculator.

 

[Randy Holmes-Farley Verified Community Expert]

Sorry to nag you but, would you know how much water impurity or percentage of water is in the instant ocean salt mixes, it's for a salt calculator.

Sorry, no.

If the purpose is to make salt mixes by mass, I am not aware of that info.

 

[SaltwaterGuruNeeded]

Sorry, no.

If the purpose is to make salt mixes by mass, I am not aware of that info.

Aww, well thank for the other info, I appreciate it alot. Keep making people happy!