Blue Green Algae How Treat the Beast

Published on 13 March 2024 at 17:43

Algae Or Bacteria?

Cyanobacteria, often referred to as blue-green algae, are actually a type of bacteria rather than algae. While they were historically classified as algae due to their photosynthetic capabilities and their resemblance to algae in appearance, advances in molecular biology have led to their classification as bacteria.

Cyanobacteria are prokaryotic organisms, meaning they lack a true nucleus and other membrane-bound organelles typical of eukaryotic organisms like algae. They are capable of photosynthesis like plants and algae, using sunlight to produce energy, but they are more closely related to bacteria in terms of their cellular structure and genetic makeup.

Despite being classified as bacteria, cyanobacteria share some characteristics with algae, such as their ability to produce oxygen through photosynthesis and their often filamentous or colonial growth forms. They can also form blooms in aquatic environments, which is why they are commonly referred to as blue-green algae.

The photosynthesis of Cyanobacteria

Cyanobacteria, despite being bacteria, perform photosynthesis similar to that of plants and algae. The process of photosynthesis in cyanobacteria involves several steps:

1. **Absorption of Light**: Cyanobacteria contain pigments such as chlorophyll a, which absorb light energy from the sun. Other pigments, such as phycocyanin and phycoerythrin, give cyanobacteria their characteristic blue-green color and help them absorb light in different wavelengths.

2. **Conversion of Light Energy**: When light energy is absorbed by the pigments, it is converted into chemical energy in the form of ATP (adenosine triphosphate) and NADPH (nicotinamide adenine dinucleotide phosphate), which are used to power the subsequent steps of photosynthesis.

3. **Carbon Fixation**: Cyanobacteria use the enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) to fix carbon dioxide (CO2) from the surrounding environment. This is the process where CO2 is combined with a five-carbon compound, ribulose bisphosphate (RuBP), to form two molecules of a three-carbon compound, 3-phosphoglycerate (3-PGA).

4. **Calvin Cycle**: The 3-PGA molecules generated in the carbon fixation step undergo a series of enzymatic reactions known as the Calvin Cycle. In this cycle, ATP and NADPH produced during the light-dependent reactions are used to convert 3-PGA into glyceraldehyde-3-phosphate (G3P), which can be used to synthesize sugars and other organic compounds.

5. **Regeneration of RuBP**: Some of the G3P molecules produced in the Calvin Cycle are used to regenerate RuBP, ensuring that the cycle can continue. This regeneration step consumes additional ATP generated during the light-dependent reactions.

Overall, photosynthesis in cyanobacteria is a complex biochemical process that allows these organisms to convert light energy into chemical energy, which they use to produce organic molecules necessary for their growth and survival.

What Preventive Measures Are Advisable

Cyanobacteria, also known as blue-green algae, can be a common nuisance in aquariums. Here are some steps you can take to effectively get rid of cyanobacteria:

1. **Water Change**: Start by performing a partial water change. This helps remove excess nutrients that cyanobacteria thrive on. Aim to change about 25-50% of the water in your aquarium.

2. **Vacuum Substrate**: Use a gravel vacuum to clean the substrate in your aquarium. This will remove any accumulated organic matter and detritus, which can contribute to cyanobacteria growth.

3. **Reduce Lighting**: Cyanobacteria thrive in light, especially if it's too intense or on for too long. Reduce the duration of light exposure or dim the lights to discourage cyanobacteria growth. Aim for 6-8 hours of light per day.

4. **Increase Water Circulation**: Improving water circulation can help disrupt cyanobacteria colonies and prevent them from settling in one area. Consider adding a powerhead or adjusting the positioning of your filter output to create more water movement.

5. **Manual Removal**: Use a siphon or aquarium-safe brush to manually remove cyanobacteria from surfaces within the aquarium. Be gentle to avoid stirring up more nutrients into the water.

6. **Improve Filtration**: Make sure your aquarium filter is functioning properly and clean any filter media regularly. A well-maintained filter can help remove excess nutrients from the water column.

7. **Test Water Parameters**: Check the levels of ammonia, nitrites, nitrates, and phosphates in your aquarium water. High levels of these nutrients can fuel cyanobacteria growth. If levels are high, take steps to address the underlying issues, such as overfeeding or inadequate filtration.

8. **Chemical Treatments**: There are various chemical treatments available specifically designed to combat cyanobacteria. These may include antibiotics like erythromycin or algaecides containing ingredients like copper. Follow the instructions carefully when using these treatments and be cautious, as they can harm other organisms in the aquarium and disrupt the balance of your tank.

9. **Promote Competition**: Introducing plants or algae that compete with cyanobacteria for nutrients can help control its growth. Fast-growing plants like hornwort or floating plants like duckweed can help absorb excess nutrients and shade the substrate, making it less hospitable for cyanobacteria.

10. **Maintain Good Aquarium Practices**: Regular maintenance practices such as not overfeeding, removing uneaten food promptly, and keeping the aquarium clean can prevent cyanobacteria from becoming a problem in the first place.

Remember that it may take some time and effort to fully eradicate cyanobacteria from your aquarium. Consistency and diligence in maintenance practices are key to keeping it under control.

When And Where Blue-Green Algae Can Appear

Generally, BGA likes to settle in low-flow areas of the aquarium. This may well have a trivial reason. Because BGA hardly adheres to the colonized surface, zones with a stronger flow seem unsuitable for colonization. Apart from such strong flow areas, BGA feels comfortable settling almost everywhere.

  1. BGA in the substrate

Often, Blue-green algae can be discovered first between the aquarium glass and the substrate before they appear elsewhere in the aquarium. The growing conditions seem particularly good there, with relatively little water movement and plenty of available nutrients in the soil and from decomposing organic waste.

  1. Weakened Biological Ecosystem

In addition to the aquarium filter, all other inside aquarium surfaces - aquarium glass, substrates, hardscape, plants, etc. - also provide a colonization surface for the bacteria that are important for the biological equilibrium.

BGA may start spreading if the "good" nitrifying bacteria do not use parts of the filter media and other available surface areas for whatever reason. Most reasonable for such bacterial-free surfaces include a recently set up aquarium, new hardscape, new plants, and using bacterial destroying drugs for livestock treatment. You should know that some medical preparations do not only eliminate the disease-causing pathogens but also the beneficial bacteria!

  1. Nutrient Imbalance Between Nitrate (PO4) And Phosphate (NO3)

Experience has shown that a nitrate deficiency with simultaneous phosphate excess can also be responsible for increased BGA growth. Nitrate and phosphate belong with potassium (kalium) to the macronutrients and are consumed more significantly by the plants than the micronutrients. A nitrate deficiency not only slows down the plants' growth enormously but other nutrients, such as phosphate, can no longer be metabolized by the plants (law of the minimum). Everything that is not consumed is available to the BGA and algae as a nutrient source.

  1. High Water Temperatures

Bacteria love a warm environment and can increase as temperatures rise. Of course, this also applies to BGA. With rising water temperatures, unfortunately, the conditions for BGA also improve, which can become problematic, especially in the summer months. If your livestock allows it, we recommend keeping the aquarium temperature below 24 °C.

Legend Ezella & BacLegend Anti-Cyano KittoPolly Can Be Used In Case Of BGA Infestation