Common name: Cyanobacteria
Cyanobacteria, often referred to as blue-green algae, are a diverse group of photosynthetic microorganisms found in a variety of aquatic environments, including saltwater aquariums. Despite their name, they are not true algae but are bacteria capable of photosynthesis. Cyanobacteria are known for their resilience and ability to thrive in various conditions, which can make them both a fascinating study subject and a potential nuisance in aquariums.
In the context of reefkeeping, cyanobacteria can appear as slimy, often brightly colored mats that cover substrate, rocks, and even corals. They are known for their rapid growth and can quickly become problematic if not managed properly. The presence of cyanobacteria in an aquarium is often an indicator of nutrient imbalances, such as excess nitrates or phosphates, and can be exacerbated by poor water circulation or inadequate filtration.
While cyanobacteria can contribute to the nitrogen cycle in natural ecosystems by fixing atmospheric nitrogen, in aquariums, their unchecked growth can lead to oxygen depletion and harm other tank inhabitants. Managing cyanobacteria involves improving water quality through regular water changes, enhancing filtration, and ensuring proper circulation. Additionally, reducing nutrient levels by controlling feeding and using phosphate-removing media can help prevent their proliferation.
For hobbyists, understanding the role of cyanobacteria in both natural and artificial ecosystems is crucial. While they can be beneficial in some contexts, such as in refugiums where they help process waste, their presence in display tanks is generally undesirable. Identifying and addressing the underlying causes of cyanobacterial blooms is key to maintaining a healthy and balanced aquarium environment.