The problem of brown algae is actually one of the very first that aquarium enthusiasts will find themselves facing, especially when it comes to newly created aquariums. The dusty brown film that it creates on glass surfaces, as well as on gravel and aquarium decorations, can actually give the impression that the aquarium itself is under-maintained. Although it might seem rather ominous at the onset, it is actually a fairly harmless and temporary condition that most aquarium enthusiasts will find themselves facing regularly. It is most often found during the initial stages of water stabilisation, especially during the early development stages of an aquarium that actually lacks the full development that it needs.
What brown algae actually are in aquariums and common signs
The brown algae that accumulates in fish tanks is actually not algae at all. Brown algae is actually composed of microscopic organisms known as diatoms. Diatoms are single-celled organisms that produce shells out of silica and can easily accumulate on surfaces. When exposed to light from aquatic lighting systems, diatoms can be distinguished from brown or rust-colored clumps forming on glass surfaces, fish tank substrate, rocks, and leaves of live aquatic plants. Brown algae are most prevalent in new fish tanks with water chemistry that is still not set.Common signs of brown algae in a fish tank:
- Thin brown or tan film on glass and decorations
- Dust-like coating on gravel rather than slimy growth
- Easy to wipe away but quick to return
- Most noticeable during the first few weeks of a new setup
Why do brown algae develop in fish tanks
Brown algae will grow when there is an abundance of silica, nitrates, and nutrients. Silica can be found in tap water and can be utilized for replication by diatoms. Newly established aquariums can be affected easily as beneficial bacteria are gradually forming colonies. Reduced lighting can also promote the development of brown algae, as green algae and plants have difficulty competing for nutrients.
Factors that encourage brown algae growth
- High levels of silica in tap water or sand substrates
- Higher nitrates from over-feeding or over-stocking
- Occasional water changes
- Poor and inconsistent lighting
- Immature Biological Filtration
- Whether brown algae is toxic to fish
Brown algae are not harmful to fish, aquatic plants, and other invertebrates when kept in moderation. Several aquarium species even tend to naturally graze on it. Nonetheless, an overgrowth may lead to the blocking of light for plants and poor aesthetics for the aquarium. Although it is nontoxic, it is deemed unwanted for an aquarium setup.
How to remove brown algae effectively
Brown algae is easily removed because diatoms do not adhere well to surfaces. Glass and decorations can be easily cleaned by rubbing the surface with a soft sponge or cloth. The gravel must be thoroughly vacuumed because diatoms tend to collect in the bottom areas of the tank. It is important to regularly siphon this algae during partial water changes to suppress rampant growth.
- Clean glass carefully
- Vacuum gravel during every water change
- Clean filter media with aquarium water
- The ornaments that are touched by the contaminated water should
- Fish and invertebrates controlling Brown Algae
Some species will naturally graze on diatoms, helping with long-term control. For freshwater aquaria, Otocinclus catfish or Bristlenose plecos are good algae-controlling species. For saltwater, Nerite snails, Trochus snails, or Turbo snails will help maintain a clean surface. All of these species must be measured for tank space appropriateness and compatibility.
Preventing brown algae from returning
Long-term prevention requires stable water conditions. Sufficient lighting promotes plant growth. This helps to continually compete with the diatoms for nutrients. Partial water changes are necessary to reduce nitrates as well as silica. If the tap water is mineral-rich, reverse osmosis water is advisable.
- Long-term prevention tips
- Give 8 to 10 hours of continuous light per day
- Don’t overfeed fish
- Conduct partial water changes regularly
- Filter or reverse osmosis water if necessary
Allow new tanks time to mature naturally – The purpose at this point is to keep a well-balanced home aquarium. If brown algae is found in a new aquarium or a newly set-up ecosystem, then it may not always denote a problem, but could simply indicate that it is still adjusting. When beneficial bacteria and a balanced water chemistry environment are created and achieved, then diatoms tend to dissolve on their own eventually. With constant care and attention, a clean and healthy environment can easily be achieved and maintained.
