How can I get rid of Cyanobacteria?

In some conditions, Cyanobacteria can form thick mats on rocks and sand in the aquarium. The same process happens periodically in natural coral reefs, but in the aquarium it becomes unsightly and if left untreated can smother and kill corals.

If your sample contains evidence of mat-associated Cyanobacteria, or if you see visible cyanobacterial mats in the aquarium, you might wish to consider the following tips for reducing their abundance.

  1. Manual removal – we consider this an essential part of any Cyano cleanup strategy. Remove heavily impacted rocks from the tank and scrub thoroughly in a bucket of saltwater. Vacuum clean the substrate using a siphon.
  2. Increase nitrate levels by about 5-10 ppm. This can be accomplished by directly dosing Sodium Nitrate or Potassium Nitrate, or by increasing the amount or frequency of your feedings with a low-phosphate food.
  3. Increase microbial diversity by inoculating your tank with a natural product like live rock, live mud or live sand.