STRESS !! a fish takes in the salt water removes the salt and takes in the water. a lower salt lever makes it easy. If you tamper with the way the fish lived prior to your tank, it can stress the fish. So the idea is to make the tank the same as it was in the wild. A fish and live in .10-.12 for a time of 2 weeks for qt. but it takes almost 5 days to bring the qt tank up to .20 or more so you and put it in the main tank. I AND I STRESS I run a 20 gal QT tank at .12, 8.2 ph and 78* why ??? is because i take a day to move the fish from the store water to the QT . I once bought a golden puffer at ??????? thinking that a puffer is a tank. Well the store has a ich attack, and the puffer got it after I took it home. I did not QT did a 3 hour drip and put her in. THE RESULT WAS DEATH. So kepp the main at .22-.24 solid and buy a refactometer, a good on and make sure the refill water has aired and you have made sure the ph and salinity are good before addin. ph can take 24 hours to change when adding new water. Sorry I droped a bomb but I always tell people to buy a 30 gal, set it up, dont by a fish over $10 and have fun for 3-4 month. after everything died, crashed or the other I ask what di you learn? And everyone had an anwser. So i say turn the 30 gal in to a sump, set it up and call me in 2 month.