Hey all. I have a well established tank, several years old. About a month ago I put down a new layer of sand. I used caribsea dry and I rinsed it very well. I figured I would get a diatom bloom, but nothing until a few days ago where now I have a nasty diatom outbreak all over the sand. Is it normal for the diatom bloom to take nearly a month to happen? I figured it would have started earlier. I’m just trying to figure out if the bloom is due to the new sand or something else possibly.