I have been dealing with a lot of cyanobacteria on my sand bed Brown and red, and brown on the rocks with little bubbles. I turned off my skimmer for 4 hours every night my nitrates and phosphates are very low I have a huge refugium with lots of Cheeto. I took out some of my Cheeto. I used dr. Tims refresh twice it has helped a little bit but I'm a little concerned I don't do water changes but every 3 weeks to a month, because my nitrates and phosphates are so low. My nitrates are like 3 to 5, and phosphates. 03 Does anybody have any suggestions ? I did two doses of chemiclean about a month ago that did help but it's back again.