Skimmate and salinity

[Cory]

I skim my tank on the wet side, the skimmate is usually dark yellow. I get about half a liter per day of wet skimmate. Just came to my mind if some of the ions would get unbalanced this way? I know I'm slowly reducing the salinity via wet skim and subsequent auto water too up, but should I be concerned about ionic imbalances?

Reason I ask is because Ron Shimmick did an article about what's in skimmate, and I remember skimmate is concentrated in other ions, like aluminum.

 

[Randy Holmes-Farley Verified Community Expert]

Skimming won't imbalance the major ions, such as chloride, sulfate, magnesium, calcium, sodium, etc.

It will export some elements that are part of organic molecules or particulates of various sorts.

 

[Cory]

Ok. So if I set skim a liter of water, just add back a liter of full strength seawater?

 

[Randy Holmes-Farley Verified Community Expert]

Yes, the salinity of skimmate is generally pretty close to tank salinity.