Got a question, I need to treat my tank with aquairum salt for external parisites it said in one of the sticky's to raise the salt level to 3%. My problem is i dont know how much salt is in the tank now because I've used salt in the past, I found my old SeaTest gravity meter but don't know where the reading should be it measures from 1.017 to 1.027. could some one tell me what it should read to be at 3% salt ?