Last Monday I started an experiment with the anti-algae product “Vibrant.” Instead of my weekly program of cleaning tank ornaments and sand, I just stuck with my usual 9 litre water change and added 10 ml of Vibrant.
This week both the cyanobacter and the green algae have increased. The black algae that adheres quite firmly to the glass has grown dramatically also. The black spot in this picture, about 1/4 of the way in from the left and 1/4 from the bottom is about twice the size of last week’s photo, and there are more spots on the back of the tank.
You can see from this photo that the cyanobacter is becoming quite thick on the sand.
At this stage, I am not too worried. This is probably about the amount of algae that I would expect to be seeing if I had skipped my cleaning last week. I expect that as the population of algae busting bacteria builds up, then the algae, including the cyanobacter, should start to decline.