Adding salt to top off water?

[Mann2021]

Hi,
another rookie question here......I'm aware new salt must be added with water changes...........because you're removing some in the process.

but does salt have to be added to the top off jug below? I was thinking the salt
in the tank remains when evaporation occurs meaning the make up water should not have salt.....just pure RO water.....is this correct?

I read some where about someone either doing it or recommending salt here in their makeup water tank .....it stuck in my mind to ask...... I thought I'd better ask people that know! 👌

Thanks in advance!!

[Aiken Drum]

Im not a salt water person, but in case nobody with more knowledge than me jumps in, my understanding is you dont add salt to make up water for the very reason you mention. The salt gets left behind when the water evaporates.

Could be wildly wrong though when it comes to saltwater. Could be wildly wrong on literally everything actually.

[BigRedsReefs10]

No just top off with ro/di, the salt stays behind in the tank.

[bribo12]

The point of topping off with freshwater is so the salinity doesn’t rise as water evaporates. Is salt left as water evaporated there wouldn’t really be a need for topping off other than to keep the water level.

[Andy Sager]

Originally Posted by Aiken Drum

Im not a salt water person, but in case nobody with more knowledge than me jumps in, my understanding is you dont add salt to make up water for the very reason you mention. The salt gets left behind when the water evaporates.

Could be wildly wrong though when it comes to saltwater. Could be wildly wrong on literally everything actually.

Just to ease your mind, YES, only the H and O evaporates, not the salts so you only top off with fresh water/RO water.

[melosu58]

Thanks for setting us straight Andy.