Considering you dont know what the salinity was and we dont know size tank, im guessing around 55 to maybe 60 gallons with sump if its the 42gallon, if salinity is at 1.025 then it could be around 1.022. Since we dont know if they even mixed properly, could be lower or higher. Plus this is a rough estimate. Tgis would be to low unless fish only. This LFS is going to hurt your tank and progress it seems. If you do hire make sure tgere is a claus that they will replace anything that happens on tgeir dime. Did you ordee a refractometer and calibration fluid yet? Also is there another lfs near by?Also I asked the LFS if I needed to be concerned about the salinity since the ATO pumped four gallons of distilled water into the sump and I was told it was not enough to make a difference on the salinity.