ATO diluting salinity

[wmcinnes]

On my 90 gallon system with herbie overflow I have been having issues where I cannot seem to match water coming down the drain with water going up into the display. The fluctuating water level in the return section of my sump is causing premature top off and is, therefore, diluting my salinity. Is there any solution to this?

Im running a JBJ Auto Top off system with a Aqualifter pump and my float switch is located in the return section.

Has anybody else had this problem? Any insight would be appreciated, thanks!