Hi, I'm about st my wits end. I cannot get rid of this algae. I'm assuming it's Cyano but not 100% sure. It comes off sand bed in a "sheet" if I'm careful when I remove it. I have siphoned the sand multiple times, water changes, lights out for 72 hours. It always comes back. Is there a way to know if it's definitely Cyano? It seems too dark for diatoms. Unfortunately, I'm having some health issues and cannot stand for very long. So I'll have to have a friend help with whatever suggestions y'all have. Thank you.