I am designing a new water mixing station. This is for a fish only set up that will run at 26 ppt (1.020 SG). I want to design it that I can throw one 50 gallon bag in and have hit mis up to that salinity. What water volume is needed? I figured it to be 61.5 gallons with a 50 gallon salt bag to make 26-27 ppt saltwater. Can anyone double check that for me?