No salt needed?

[tdowning]

So after having a nano tank for the past year and not really having to worry about evaporation, I moved into a 150g tank w/ 55g sump. I'm now losing 1-3 gallons of water per day to evaporation and for the first 6 weeks I couldn't figure out why my salinity levels were so high...then it hit me (and correct me if I'm wrong) but I can just add fresh RO water on my daily top off since when my water evaporates, the salt does not. So, again and please correct me if I'm wrong, the only time I'll need to add salt to my RO is when I'm doing a water change...otherwise I can just add fresh RO water each day that I top off my system?

 

[cmcoker]

You are correct, no salt for topoff, only use saltwater for water changes

 

[Randy Holmes-Farley Verified Community Expert]

There may be other times when you need to add or remove salt (skimmers remove it, two part additives add it), but certainly, replacing evaporation should either be with pure fresh water, or with pure fresh water plus additives that you know you need to add.