Testing is something I always recommend to anyone, especially if their tank is seemingly off. But what about testing when everything is right? When talking to Joe Yaiullo of the Atlantis Aquarium (formerly the Long Island Aquarium), he mentioned how he tests repeatedly to make sure the results he gets are accurate. Specifically, if salinity is dead on, he tests again and again to make sure that it's actually correct and not a false sense of security. As he pointed out, when we see the numbers we like, we don't retest.