Sump setup problems need help

[caxcrew]

I need some help with my sump setup on my 75 gallon salt water sounds weird but the water is evaporating or something I keep adding saltwater but when it’s added to the sump and I come back later the sump is low and these air bubbles our spewing out is it too much flow there’s also a milky film occurring also Help

 

[BIG-G]

To much turbulence and bubbles will cause a lot of evaporation when these bubbles bust they throw salt into the air that can accumulate on any surface nearby.(Salt Creep)
The smoother you can get the flow through the sump the better.
Also if you’re not make sure you are replacing water with freshwater not saltwater.
If you are replacing with saltwater your salinity will increase In the tank.

 

[Oughtsix]

Exactly what BIG-G said, especially the part about replacing with fresh water, not salt water.

If the water level is going down a lot faster than you think it should I would triple check the whole setup for a slow leak!