Saltwater tank Evaporation.

[Garryzoanthid]

Hello,

I was wondering if anybody knew about salinity dropping when adding fresh water into an evaporated fish tank. Now what I’m dealing with is that half of my saltwater fish tank was evaporated. Although I know that evaporated saltwater just leaves salt behind. So I’m just wondering if anybody knows if the salinity drops or stays the same when adding freshwater to an evaporated saltwater fish tank. I even plan on doing a water change. I have live fish in the fish tank aswell.

 

[Homebrewer]

Sounds like you have a reasonable understanding already.

Tank water evaporates, leaving it slightly saltier… you top-off with fresh water, diluting the slightly saltier-ness, bringing the tank back to normal levels.

 

[Townes_Van_Camp]

Yes it fluctuates.

As water evaporates, the salinity/sg increase.

When evaporated water is replaced/topped off with RODI in an amount equal to evaporation, the sg will return to where it was.

 

[Garryzoanthid]

Yes it fluctuates.

As water evaporates, the salinity/sg increase.

When evaporated water is replaced/topped off with an amount equal to evaporation, the sg will return to where it was.

So would I simply just have to add freshwater to the fish tank to keep it at the same level as it was before it was evaporated?

 

[Homebrewer]

So would I simply just have to add freshwater to the fish tank to keep it at the same level as it was before it was evaporated?

Yes

 

[edd59]

thats why you need an auto top off. the fluctuating is not good for your live animals.

 

[ColoredRock]

Most of BRS videos are infomercials designed to sell a solution IMHO but the do put out good info as well.. this is a good explanation.

 

[TX_REEF]

Definitely look into getting an ATO; there are plenty of cheap options that will saves you tons of time, effort and salinity fluctuations!