Salinity question

[Ghostyboythedog]

Hi,
I have a 20 gallon saltwater tank. I did a water change and I filled it with ro water. I have a salinity gage, and every time I do a water change the gage goes down. Am I supposed to do haft saltwater and ro?

 

[lil sumpin]

When you do a WC, you wanna add water that matches the temperature and salinity (and also resembles parameters) of your tanks water. Adding RO water will make your salinity lower.

 

[19Mateo83]

For water changes you use saltwater that is mixed to 1.025/1.026.
For topping off evaporation you use plain RO water because the salt does not evaporate

 

[gbroadbridge]

Hi,
I have a 20 gallon saltwater tank. I did a water change and I filled it with ro water. I have a salinity gage, and every time I do a water change the gage goes down. Am I supposed to do haft saltwater and ro?

When you do a water change you replace the water with freshly mixed salt water not RO water.

You only use RO water to replace evaporated water.

 

[Reef.]

When salt water sits in your tank, you will loose some water to evaporation, the salt stays in the tank, just the plain water leaves the tank, so you need to add more plain water to top up your tank to the level it was previously so the salinity stays the same.

When you do a water change, all you are doing is taking out a bucket of dirty salt water and replacing it with exactly the same amount of salt water at the same salinity.

Topup = plain rodi water
Water change = Salt water at the same salinity as the tank 1.0264 or 35ppm.