Adjusting SG/Salinity

[jejton]

Is there an easy and practical way of calculating how much water or salt mix needs to be added to a volume of water in order to adjust the SG/Salinity up or down? I know there is a methodoligical way to do it but I am looking for a practical way ( besides by guesswork )
without having to go find my chemistry textbook.

 

[Deanos]

One of these SaltyZoo Calculators should work.

 

[NYreefNoob]

different salts need different amounts to get you to a certain salinity. i use a measuring cup to add to ro water and after slowly adding to figure out how much is needed to get where i need

 

[jejton]

Thanks Deanos that will do the trick.