Soo I’ve been away for 2 weeks on holiday and have come back to a tank covered in this algae..I’m worried it’s blue-green algae and dangerous. Is it safe to clean out the tank? The fish are all okay still luckily!
Yes it's blue green algae (Cyanobacter bacteria). You can safely gravel clean and syphon out as much as possible. You usually have to do this every day for a few weeks to get rid of it.
