Green Hair Algae Control In Freshwater Aquarium
Green hair algae, also known as filamentous algae are single algae cells that form long visible chains, threads, or filaments. Some are attached (epiphytic), some are free floating. There are many species of Green hair algae (dozens if not hundreds) that can find their way into the aquarium or pond. Each of them have various names that only contribute to the confusion. For that reason, it is very difficult to pinpoint the exact reason why each of them grow and how to control their growth. So what I did here is to browse the many articles about Green Hair Algae and tried to come up with a “general” guide with general guide lines. I don’t claim this is all you should know about Green Hair Algae, it’s just what I could find. If anyone of you can add to this, please do so using the comment box bellow.
The Most Common
Some of the most common species (or genera?) of Green hair algae that are commonly seen in the aquarium hobby are Spirogyra, Cladophora, Oedogonium and Pithophora.
Spirogyra: Spirogyra is a genus of filamentous green algae of the order Zygnematales, named for the helical or spiral arrangement of the chloroplasts that is diagnostic of the genus. There are more than 400 species of Spirogyra in the world. In general, this kind of algae can be easily identified by its bright, neon-green color. At the microscopic level, this algae resembles a DNA helix. It is very slimy. In spring Spirogyra grows under water, but when there is enough sunlight and warmth they produce large amounts of oxygen, adhering as bubbles between the tangled filaments. The filamentous masses come to the surface and become visible as slimy green mats.
Cladophora (Aeragropila): A filamentous algae that look like cotton. Cladophora resembles tiny plant-like stalks that undulate and look “hairy”. This is an unattached algae. It is only a problem for tanks with high nutrients and without water
circulation.
Pithophora: Also known as Thread algae, Staghorn algae or Horse hair algae, Pithophora is a genus of the Cladophoraceae. It is the one that forms irregularly branched threads from an attachment point. It grows in very long thick strands and resembles thick long hair and feels like wool. It seems to flourish with excess micro nutrients like iron. A few water changes and reduced feeding will bring the nutrient levels back to normal (and eventually starve the algae)
Oedogonium: This is probably the algae people are calling fur algae. It spreads very rapidly and prolifically by means of flagellated cells, and covers leaves of plants and other objects in a dense coat of unbranched hairs, about 2 to 5 mm. long.
Possible Causes & treatment
Here are some of the most common cause and treatment I have found looking on the Internet. I suggest you give each change a month or so to see improvements or not.
1) Nutrient:
Nutrient problems (nutrient imbalance, deficiency or excess) are easy to eradicate and this is probably what you should look at first. In a non-planted aquarium, test for nitrate and phosphate. If those two are very high, a few water changes and a better maintenance routine will certainly help lot. In a planted tank, dosing EI will rule out the possibility of nutrient deficiency and/or imbalance while you sort out the cause of the problem.
2) Water flow:
Nutrients often build up in areas with low water movement. Increasing the flow will help prevent local build up of nutrients.
3) Co2 & nutrient vs Light:
I won’t cover the whole Co2/nutrient vs Light topic here. To make a long story short, a balance of light and CO2/nutrients must be maintained in the aquarium. If you increase either the amount of light, or the available nutrients without also increasing the CO2, algae will get the upper hand. Either reducing the photo period, reducing the light intensity or adding more Co2 can help lot.
4) Excess iron in the water:
According to what I found, Green hair algae will quickly take advantage of an excess in iron in the water. High iron normally results from excess fertilization, but some water supplies have high iron levels (especially well water).
5) Manual Removal:
Manual removal is a good way to get rid of Hair Algae. Manual removal will work, but it will not keep the algae from coming back in the future.
6) Algae Eater:
There are fish out there reported to eat Hair Algae. American Flag Fish and Cherry Barbs are some of them. Have a look to my other post call Best Algae Eaters For The Freshwater Aquarium for more information. Keep your algae eaters hungry and they will do a better job. Again, algae eating fish will not keep the algae from coming back in the future.
Conclusion
As said at the beginning of this post, this is just a general overview of the most common algae called Hair Algae and a brief overview of the most common advice I could find to eradicate them. I will keep adding to this post as I find more information. In the meantime, if you can add to this (or correct some of the information) please do so using the comment box bellow.
References
Aquabase.org
What is Filamentous Algae?
Fins.com
Wikipedia: Spirogyra
TheKrib.com
Csd.net
Aquatic Plant Central
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