Evaporation question

[tntfish]

hey guys i have a 135 gallon tank and my friend was tellin me that i can add regular water instead of a whole water change how do i do this he didnt reallyy explain him self can anybody help?

 

[melosu58]

Any evaporation is replaced with FW because the salt stays in the tank. Any PWC water is SW going out and needs to have SW going back in to replace it.

 

[bavass]

water evaporates the salt does not. You don't need to add salt to water top off

 

[thincat]

I have a piece of tape on the side of my sump that shows me how much water has evaporated from my tank. I now have an Auto topoff and that replaces the evaporated water automaticly.