Cyanobacteria (BGA)
Definition
Cyanobacteria, commonly known as "blue-green algae" (BGA), are a type of photosynthetic bacteria that can thrive in aquarium environments. Despite their misleading name, cyanobacteria are not true algae; they belong to the bacterial kingdom. These microorganisms are characterized by their blue-green coloration and can often form slimy or filmy layers on various surfaces within aquariums.
Function in the Aquarium
Despite the name, cyanobacteria are not true algae. They can be a common issue in aquariums, usually indicating an imbalance in nutrient levels, and often require manual removal.
In aquariums, the presence of cyanobacteria is often an indication of an imbalance in nutrient levels. These bacteria can exploit excess nutrients, such as nitrates and phosphates, leading to their overgrowth. Poor water quality, inadequate filtration, and imbalances in the nitrogen cycle can contribute to the proliferation of cyanobacteria.
The function of cyanobacteria in the aquarium ecosystem is generally undesirable. Their overgrowth can negatively impact the aesthetic appeal of the tank, covering plants, rocks, and substrate with slimy layers. Additionally, cyanobacteria can outcompete other desirable aquarium organisms, such as plants, for essential nutrients and light.
Aquarists often need to manually remove cyanobacteria to control their growth. This may involve physically scraping or siphoning the slimy layers from surfaces within the aquarium. Taking steps to address the underlying causes of nutrient imbalances is crucial to prevent the recurrence of cyanobacterial blooms. This may include adjusting feeding practices, performing regular water changes, enhancing filtration, and promoting a balanced and stable aquarium environment.
How to control BGA?
Controlling cyanobacteria in an aquarium involves addressing the underlying factors that contribute to their growth. Here are several strategies to help control and prevent cyanobacterial blooms:
Regular Water Changes:
Perform regular water changes to dilute nutrient levels in the aquarium.
Use a siphon to remove debris and detritus from the substrate during water changes.
Proper Feeding Practices:
Avoid overfeeding, as excess uneaten food contributes to nutrient imbalances.
Feed your fish a balanced and appropriate diet, and remove any uneaten food promptly.
Enhance Filtration:
Ensure your aquarium has efficient mechanical and biological filtration.
Consider adding chemical filtration media, such as activated carbon, to help remove dissolved organics.
Prune and Maintain Plants:
Healthy and actively growing aquatic plants can compete with cyanobacteria for nutrients.
Regularly trim and maintain aquatic plants to encourage their growth and nutrient uptake.
Proper Lighting:
Ensure that the aquarium receives an appropriate amount of light for the specific plants and inhabitants.
Consider using a timer to regulate the lighting duration to mimic a natural day-night cycle.
Algae Eaters:
Introduce algae-eating organisms, such as certain species of fish (e.g., Siamese algae eaters), snails, or shrimp, which can help consume cyanobacteria.
Hydrogen Peroxide Treatment:
In controlled and cautious amounts, hydrogen peroxide can be used to spot treat cyanobacteria.
Turn off aquarium equipment, apply hydrogen peroxide directly to affected areas, and wait for a brief period before turning equipment back on.
Adjust Water Parameters:
Monitor and adjust water parameters, such as pH and temperature, to ensure they are within the appropriate range for your aquarium inhabitants.
UV Sterilization:
Consider using a UV sterilizer to help control free-floating algae and bacteria in the water column.
Quarantine New Additions:
Quarantine new plants, fish, or equipment before introducing them to the main aquarium to prevent the introduction of cyanobacteria.
It's important to note that consistency is key when implementing these strategies. Regular maintenance and monitoring of water parameters will contribute to a healthier aquarium environment and help prevent cyanobacterial overgrowth.
