If it is a fish only tank and your salinity is lower or equal to what the salinity is in the bag, then once the temperature is equal in both tank and bag , then I add the fish to my QT tank. For reef tanks, where the salinty is around 1.25 or 1.26 . most fish wholesellers and fish stores keep their non reef fish tank at a lower salinty like 1.19 , when you are adding fish where the salinty is higher than where they were obtained, it is less stressfull for the fish to follow the drip method, the bigger the difference in salinity , the longer the acclimation period.