General description: It is green in color, slimmy and smelly. It doesnt really belongs to the algae family but is rather a type of cynobacteria. BGA spread very fast and it doesnt take long for them to conquer the whole tank.
Possible causes:
1. Insufficient nitrate
2. Poor water circulation
Countermeasures:
1. Dose nitrate directly into the tank
2. Reduce lighting hours and if possible, switch off all lighting (black out)
3. Treat with Seachem excel - Fill a syringe with excel and then apply directly at the affected area (warning, some plant will melt in close contact with excel )
4. If all of the above not working, time for anti-biotic (Note you need to seed your filter after antibiotic regime)
3. Chladophora
General description: It is usually in green and it is one of the toughest algae to remove. It is tough and it looks like a chunk of wool. It loves to stick on plants, substrate and hardscape.
Possible causes:
1. Insufficient CO2
2. Insufficient nitrate
3. Presence of Morimo ball
Countermeasures:
1. Increase CO2 and nitrate
2. Manually removal
3. Treat with Seachem excel - Fill a syringe with excel and then apply directly at the affected area. (warning, some plant will melt in close contact with excel )
4. Amano/Yamato Shrimps and SAE will eat it (you may need to starve them though)
4. Diatoms
General description: According to Indiana University, Biology department, diatoms are unicellular algae generally placed in the family Bacillariophyceae. From what we know, diatoms algae are brown in appearance and usually seen in the early part of setup (about 4-12 weeks)
Possible causes:
1. Insufficient of light
2. New tank setup
Countermeasures:
1. If possible, use a small hose to siphon off the diatoms
2. Manually removal by scraping off the diatoms
3. Otocinclus will eat it
5. Green Dust Algae (GDA)
General description: It is green in color and it looks exactly like dust sticking onto stones, driftwood and tank glass.
Possible causes:
1. Zoo-spores
2. Too much lighting
Counter-measures:
1. Scrap or clean off the green dust algae with a help of toothbrush, scraper or cottom wood
2. Do 30% water change until problem clear
3. Reduce lighting hours and do switch off lighting for 48 hours if necessary (black out)
6. Green Water
General description: It is a type of algae which appears in newly setup tanks. This algae makes the aquarium looks very green as if the water is green in color.
Possible causes:
1. Excess Ammonia in water
2. Too much lighting
Countermeasures:
1. Add in a UV sterilizer
2. Do 30% water change until problem clear
3. Reduce lighting hours and do switch off lighting for 48-72 hours if necessary (black out)
7. Hair Algae
General description: It looks exactly like human hair but is much thicker. If left unattended, it can grow rapidly in tanks.
Possible causes:
1. Low CO2
2. Ammonia spike
Countermeasures:
1. Change 30% of the water
2. Treat with Seachem excel - Fill a syringe with excel and then apply directly at the affected area. (warning, some plant will melt in close contact with excel )
3. Manual removal - Remove them with the help of a tweezer or tooth brush
4. Amano/Yamato shrimps, SAE, Rosy barbs and Mollies will eat it (you may need to starve them)
8. Green Spot Algae
General description: It is green in color and it loves to grow on slow growing plants and on the aquarium glass. Once you see some stubborn green spots on the tank glass, that is likely to be green sport algae.
Possible causes:
1. Insufficient phosphate (PO4)
2. Insufficient CO2
3. Too much light (closely related to point 2)
Countermeasures:
1. Scrap off the algae on your glass with a hard card or cotton wool
2. Add phosphates
3. nerite snails
4. Increase the amount of CO2 injection
9. Staghorn Algae
General description: It usually grows into a clump in certain part of the aquarium. This algae grow pretty slowly but if it is allowed to grow, it will form a carpet.
Possible causes:
1. Insufficient CO2
2. Poor water circulation
3. Dirty filter
Countermeasures:
1. Change 30% of the water
2. Increase the amount of CO2 injection
3. Manual removal by cutting the infected area
4. Maintain proper fertilisation regime (Dose sufficient NPK)
5. Clean your filter
Conclusion
Whenever the word "algae" is mention, some will worry and tries to use a lot of method to prevent it. In Sun Tze's Art of War, it is mentioned 知彼知己，百戰不殆；不知彼而知己，一勝一負；不知彼，不知己，每戰必殆. It means that if you know your enemies and yourself, you will not imperiled in a hundred battles; if you do not know your enemies but know yourself, you will win one and lose one battle; if you do not know your enemies and yourself, you will be imperiled in every single battle.
To us, algae is a kind of "indicator" to monitor our aquascape status so we have to understand it well and treat every algae attack as a learning experience. Don't bother about trying to limit algae grow, you can't limit them because they only need very small amount of nutrient to grow. Instead try to focus on plant health, somehow healthy plant reduce the change of algae spore germination.
Lastly, when you have an algae attack, dont panic as algae is always a "good" friend to maintain a healthy aquascape. We may sounds crazy but we really enjoy our battle with algae.
