[bertoni]

Most of the animals should tolerate a brief drop to 1.019 SG, but corals and other invertebrates will be affected more than fish. Fish can regulate their internal SG, so they have more of a buffer. I'd bring the SG back up over a few days or so. That's a bit faster than I'd usually recommend, but the animals haven't been at that SG for long, and 1.019 is very low for corals.