Been having problems with Cyanobacteria. My tank was looking horrible yesterday morning. Sand all red, lots of red spots of rocks. Added 1.7cc of Nualgi at about 4:30 when the mail came. Left on LED lights on so that I would get more than the 4 hours of lighting to start the Diatom growth, was up in the middle of the night to turn the lights off (so I wouldn’t burn any corrals) and the cyano is gone from the display tank. I didn’t check the refugium yet, but amazed. I didn’t get as good a result when I recently used Chemi-clean. Photos soon.