Common name: Bacteria
Bacteria are microscopic, single-celled organisms that are incredibly diverse and can be found in virtually every environment on Earth, including in reef aquariums. They play a crucial role in the nitrogen cycle, which is vital for maintaining healthy water conditions in aquariums. In reef tanks, beneficial bacteria help break down waste products, such as ammonia and nitrite, into less harmful substances like nitrate, which can then be utilized by plants and algae or removed through water changes.
Bacteria in aquariums can be categorized into aerobic and anaerobic types. Aerobic bacteria require oxygen and are typically found in filter media and on surfaces within the tank, where they help convert ammonia into nitrite and then nitrate. Anaerobic bacteria, on the other hand, thrive in low-oxygen environments, such as deep sand beds or within porous live rock, where they can further process nitrate into nitrogen gas, which escapes harmlessly from the system.
For aquarists, establishing a stable bacterial population is essential for a balanced ecosystem. This process, known as cycling, involves allowing the tank to mature over time so that beneficial bacteria can colonize and maintain the nitrogen cycle. Products containing live bacteria cultures are available to help speed up this process.
While beneficial bacteria are key to a healthy aquarium, harmful bacteria can pose risks to fish and invertebrates. Regular monitoring and maintenance, including water testing and proper filtration, help keep harmful bacteria in check while promoting the growth of beneficial strains.