I have a 20 gallon all natural seawater and after the hurricane ian I've done a beach cleanup in my favorite beach and found chemicals that lead me to worry about the condition of the sea im overdue from Saturday before the storm to do a water change but I does a 50% water change if I use synthetic sea water is that goin to lead to any effects I should worry bout but i will have to get the salinity as close as possible for sure if its ok