Algae in the Planted Aquarium
February 29th, 2008Introduction
Every aquarium keeper has likely had to deal with an algae problem. In a planted aquarium, an even more complex set of variables can easily go out of whack, and end in a sad algae state. I’ve combined information from a few different websites, added some personal experience, and have hopefully assembled a complete reference for the most common types of algae seen in the planted aquarium, along with their causes and cures. This is an ever-evolving document, so if you feel anything is incorrect or misleading, please don’t hesitate to leave a comment with your correction.
Table of Contents
Black Brush/Beard (Rhodophyta)
Brown Algae (Diatoms)
Blue Green (Cyanobacteria)
Cladophora
Fuzz Algae
Green Dust Algae (GDA)
Green Spot (Choleochaete orbicularis)
Green Water (Euglaena)
Hair/Thread Algae
Staghorn (Compsopogon sp.)
Black Brush/Beard (Rhodophyta)
Black brush, or BBA, algae can be one of a number of specific genera of “red” algae in the Rhodophyta family. Most of the algae in this family are actually marine, but a few freshwater species exist that particularly target our planted aquariums. This algae may be black, brown, red, or green in coloration, and can quickly coat your plants and hardscape if not kept in check.
Cause:
- Nutrient Imbalance – potentially excess N, P, Fe. Strive for the following nutrient levels: N (10-20ppm), P (0.5-2ppm), K (10-20ppm), Ca (10-30ppm), Mg (2-5ppm), Fe (.1ppm).
- Low pH – Neil Frank observes that African Rift tanks never have BBA. It’s believed that BBA thrives in acidic environments, which is unfortunately what most plants prefer.
Cure:
- Increase CO2 – This will stimulate plant growth, which should help the plants out-compete the algae for resources.
- Excel/H202 treatment – Use a syringe to spot treat problem areas. Then manually remove when BBA turns grey/white.
- Manual removal – Use toothbrush to remove as much as possible.
- Bleach treatment – Dip affected hardscape items/hardy plants in a bleach/water solution using a 1:20 ratio of bleach to water. Before putting them back into the tank, make sure the item is free of bleach odor.
- OxiClean treatment – Dip affected hardscape items in a OxiClean solution, making sure you only use the original OxiClean with no other additives.
- Maintain proper water change/dosing schedule – weekly / bi-weekly changes.
- Algae Crew – Siamese Algae Eaters (SAE) and Amano shrimp are known to eat this algae.
- Copper (not recommended) – There are commercial algaecides containing copper that will kill BBA, but they will mostly likely also kill your plants.
Brown Algae (Diatoms)
Brown Algae, or diatoms, often present themselves as a brown, muddy, muck that covers plant leaves and hardscape items. It is rare to be seen in a fully established aquarium.
Causes:
- Newly setup tank – Aquariums that have just been setup seem to be prone to diatom algae.
- Excess nutrients – Silica in particular appears to be a trigger. Contact your water utility company for a report detailing silica concentrations in your water supply.
- Possibly old bulbs – Sometimes, old bulbs can encourage the conditions for diatom algae.
Cure:
- Time – Allow it to use up the excess silica, and it will often disappear on its own.
- Manual removal – Siphon/scrape diatoms manually for quick removal.
- Algae Crew – Otocinclus and Nerite snails are fantastic at clearing a tank of diatoms. They help with other sorts of algae as well.
Blue Green (Cyanobacteria)
While often referred to by aquarists as an algae, Blue Green Algae (BGA) is in fact a bacterial slime that can easily coat everything in your tank. Appearing as either a green, black, or purple coating, BGA is perhaps best known for the unique earthy smell that it has when pulled from the tank. As a nitrogen-fixing bacteria, it will fully deplete your water column of any available nitrogen.
Causes:
- Low nitrates – Usually present when all of the nitrogen/nitrate has been removed from the water column. While this is a triggering condition, it is also exacerbated by the bacteria itself using any remaining nitrogen.
- High organics – Overfeeding, or excess organic matter in the tank can trigger BGA.
- Old light bulbs – Sometimes present when light bulbs are no longer emitting usable light. This may be more of a matter of your plants no longer being able to out-compete the bacteria.
- Poor water circulation – Circulation is key in a planted aquarium so that no “dead spots” are present where nutrients have been used up locally, but fresh ones are not being recirculated throughout.
Cures:
- Increase nitrates – Dose nitrates until the concentration reaches ~5ppm.
- Add fast growing plants – this helps to out-compete the algae for resources.
- Blackout – BGA cannot survive without light.
- Excel/H202 treatment – Use a syringe to spot treat problem areas. Then manually remove dead patches.
- Erythromycin – use antibiotics at half dosage to kill the bacteria. Mardel Labs’ Maracyn contains erythromycin and has been used effectively without harming most plants.
Cladophora
Cladophora is by far the toughest algae to remove from the aquarium. Forming green, tough, wool-like mats, it seems to favor intermingling itself into hairgrass, substrate, and hardscape items.
Causes:
- Marimo Balls – Being in the same family as these algae balls, they can sometimes introduce Cladophora to your aquarium.
- Healthy Conditions – Unfortunately, Cladophora seems to favor the same healthy water conditions that your plants require.
Cure:
- Manual removal – Use toothbrush/tweezers to remove as much as possible.
- Excel/H202 treatment – Use a syringe to spot treat problem areas.
- Luck – Very difficult to 100% remove.
Fuzz Algae
Fuzz algae often shows up on plant leaves giving their edges a slightly fuzzy appearance.
Causes:
- Nutrient Imbalance – Strive for the following nutrient levels: N (10-20ppm), P (0.5-2ppm), K (10-20ppm), Ca (10-30ppm), Mg (2-5ppm), Fe (.1ppm).
- Low CO2 – Strive for 20-30ppm concentration of CO2, as permitted by fauna.
Cure:
- Maintain proper nutrient/CO2 levels
- Algae Crew – Siamese Algae Eaters (SAE), Amano shrimp, Otocinclus, and Mollys are known to eat this algae.
Green Dust Algae (GDA)
Green Dust Algae (GDA) is a “dusty” green film that appears on the surface of the glass. It’s caused by zoo-spores, and seems to avoid attaching to hardscape items or plant leaves.
Cause:
- Unfortunately, I haven’t been able to locate a concrete cause for GDA.
Cure:
- Leave alone – GDA appears to have a finite lifecycle, so that if you allow it to run full cycle without scraping it from the glass, it should harden, and fall off after roughly 21 days. After this time, scrap any remaining GDA from the glass, and do a thorough cleaning and water change.
- Nerite Snails – Nerite snails can help eat through some of the GDA on the glass, but the approach above will likely have to be undergone for full removal.
Green Spot (Choleochaete orbicularis)
Green spot algae is very commonly seen on the glass of tanks when there hasn’t been a water change in awhile, or when an inadequate fertilization scheme has been conducted. GSA also appears on long lasting leaves, such as Java Fern, Anubias, and Bolbitus.
Cause:
- Low phosphate (PO4) levels – almost exclusively caused when phosphate levels are depleted.
Cure:
- Scrap glass – Use a razor blade to most easily remove from the glass.
- Dose Phosphates – Dose PO4 to a concentration of 0.5-2.0ppm.
- Nerite Snails – Nerite snails can help you remove green spot from leaves, as well as, the glass.
Green Water (Euglaena)
Green water is free floating single-celled euglenoid protists. It contains chlorophyll a and b, plus carotenoids, giving them their green coloration, but they are not plants. With over 40 genera of Euglenoids and over 1000 species, this form of algae is one of the most abundant forms of life on the planet, and is an essential part of the food chain. Unfortunately, aquarists don’t want it in their tanks.
Cause:
- Initial Setup – Usually present shortly after an aquarium is initially setup, prior to the full establishment of the microorganisms (free-swimming plankton that feed upon it).
- Nutrient Imbalance – Strive for the following nutrient levels: N (10-20ppm), P (0.5-2ppm), K (10-20ppm), Ca (10-30ppm), Mg (2-5ppm), Fe (.1ppm).
- Medication – if the medicine affects the biofilter of the tank.
Cure :
There are a number of cures for green water:
- Blackout – leave the lights out, and block out any ambient light from the tank for 5 days. Your plants have reserves that the algae does not, so they will survive, but may look a little ratty for a week or so.
- Diatom/Micron Filter – fine particle filters can clear the water.
- UV Sterilizer – zaps the algae with ultraviolet light, clearing the water. Some reports say that UV light also affects nutrients in the water column.
- Flocculants – Clumps small particles together, allowing your mechanical filtration to remove them from the water. i.e. AquaClear
- Daphnia – Placed in a breeder net, the daphia will consume the algae.
- Small Water Changes – do small (5-10%) water changes, every day until clear.
Notes:
- Avoid large water changes, as that prevents microorganisms from establishing themselves.
- In addition to the cures, make sure to identify and eliminate the source of the problem, or it may return.
Hair/Thread Algae
Hair/Thread Algae consists of long green filaments reaching as long as 30cm in length. It often mixes itself in among moss, and is sometimes grown purposely as an extra food supplement for tank inhabitants.
Cause:
- Excess iron levels – Concentrations >0.15ppm
Cure:
- Manual removal – Use toothbrush to remove as much as possible.
- Maintain proper water change schedule – weekly / bi-weekly changes.
- Rebalance Nutrients – Strive for the following nutrient levels: N (10-20ppm), P (0.5-2ppm), K (10-20ppm), Ca (10-30ppm), Mg (2-5ppm), Fe (.1ppm).
Staghorn (Compsopogon sp.)
Staghorn algae is aptly named as its branching resembles the antlers of a stag’s horns. They are coarse, branching strands that commonly attach to plant leaves and equipment. The strands can appear white, grey, or green in coloration.
Causes:
- Nutrient Imbalance – Strive for the following nutrient levels: N (10-20ppm), P (0.5-2ppm), K (10-20ppm), Ca (10-30ppm), Mg (2-5ppm), Fe (.1ppm).
- Low CO2 – Strive for 20-30ppm concentration of CO2, as permitted by fauna.
Cures:
- Manual removal – Use toothbrush to remove as much as possible.
- Water change – Maintain weekly/bi-weekly water change schedule.
- Increase CO2 – This will stimulate plant growth, which should help the plants out-compete the algae for resources.
- Bleach treatment – Dip affected items/hardy plants into a bleach/water solution using a 1:20 ratio of bleach to water. Before putting them back into the tank, make sure the item is free of any bleach odor.
- OxiClean treatment – Dip affected hardscape items in a OxiClean solution, making sure you only use the original OxiClean with no other additives.
- Maintain proper macro (NPK) dosing scheme
Note:
- Most fish/inverts will not eat staghorn algae.
Sources:
Aquatic Plant Central Thread
Aquatic Plant Central – Algae Finder
AquaticScape
Fighting Algae with Hydrogen Peroxide
The Skeptical Aquarist
March 2nd, 2008 at 10:01 pm
[...] Algae in the Planted Aquarium [...]
March 4th, 2008 at 11:07 pm
Cladophora is not brought to a tank by Marimo Moss Balls, Marimo Moss Balls are Cladophora. Marimo grow in either the their ball shape or as a thick mat on the bottom of the tank.
March 15th, 2008 at 12:02 pm
Thanks for the excellent resource. I now have determined that I have Blue Green “Algae” and am going to take the measures you described to irradicate this annoying problem! I’m going to try the black out first and then the erythromycin if that doesn’t do it. Thanks again for a clear “causes” and “cures” format!
March 15th, 2008 at 6:45 pm
Glad to help Patricia! Good luck with your BGA. Often times, particularly in planted aquariums, this can be easily remedied by dosing nitrate.
March 23rd, 2008 at 4:36 pm
Thanks for the info. Any info is nice to base an algae offensive on. I’ve got a 75 with only a slight green spot algae problem.
March 23rd, 2008 at 10:21 pm
Josh, green spot is one of the easier ones to remedy. Good luck, and thanks for the comments!
March 25th, 2008 at 11:32 am
Great info and a great resource!
Thanks
May 7th, 2008 at 10:33 pm
How can I get rid of the Green Water?
Every time I put my electric blue crayfish in a ten gallon tank, the water gets green. I am guessing is the food I feed it, but the crayfish always eat it completely so I am not sure if it is that. I feed him the green pebbles for plecos. I also feed it other stuff, but during the time it was in the ten gallon that was the food.
May 8th, 2008 at 5:46 am
Holy G, green water is covered in this article. Try cutting back on the amount of food you feed as a start.
May 19th, 2008 at 9:31 am
When my planted tank was running my main problem was
a thread type algae, something like staghorn. It was
a long thin thread with a tiny node or ‘bead’ every
inch or so that sometimes branched. It would quickly
spread among the stem plants. Using a small dowel rod it could be twirled and removed, but would break
easily leaving small pieces to start again. Please
what is it and how do I get rid of it. Thanks
May 19th, 2008 at 10:13 am
Morris, what you are describing, particularly the “thin thread with a tiny node or bead,” sounds more like Utricularia gibba to me, than algae. Check out the picture here and let me know if that’s it:
http://www.plantarara.com/carnivoren_galerie/utricularia/utricularia.htm
If so, unfortunately, U. gibba commonly is a contaminant when plants come in from the whole sellers, and is a bear to remove. Manually removal with tweezers is the only way I’ve ever know to get rid of it.
May 21st, 2008 at 1:47 pm
Thanks for the reply. It is difficult to be sure on the ID from the picture,
it appears to have a small
leaf or air blatter? along the stem. What I had was a pale green to
yellowish stem with small joints
every inch or so. Imagine ‘connect the dots’ with sewing thread. It would
intangle around the stem
plants, especially Rotalla and Bacopa, and spread quickly.
Perhaps I am better off than I thought since I have recently moved and
the plant tank was a fatality
due to being to far down the list of things to get done while building a new
house. I will plan to redo
the setup, hopefully better than before.
May 21st, 2008 at 5:08 pm
It sure sounds like U. gibba. If it was, those little bladders capture microorganisms to ingest, as it’s carnivorous.
July 29th, 2008 at 3:02 am
There is many times mentioned using OxiClean as remedy. As far as I know, OxiClean is effective because produces hydrogen peroxide when dissolved in water (http://en.wikipedia.org/wiki/OxiClean). So, obviously you can achieve same result with pure hydrogen peroxide which is available from any drugshop. It’s cheap and clean if we compare with OxiClean – we don’t know what exactly is inside OxiClean.
July 29th, 2008 at 5:49 am
Rein, you’re absolutely correct. I have listed Hygrogen peroxide several times above by its compound name, H2O2. The drugstore variety (3%) of H2O2 is a great spot treatment for algae.
October 12th, 2008 at 11:54 pm
i feal i may have a hidden problem an my 125 us gal. ive had every algie prob posible. tank consists of 6-t5,48in lighting 8houres day co2, 1/3 volume filteration, 1/3-1/2tank water change weakly w/ ro. ph controler kept at 7.0, temp 75deg F*, 13 bags of eco-compleet, active tds meter at60-100ppm. 2-14w uv steralizers. Ithenk that covers it, but iv had severe algie problems from day 1, about 1 year. supper bugs killed it once, in that time fore about 1 week. im moderatly to heavly plented. some fast some slow growing plants. swords, criptacorns, glosostigma, anubious, java moss, jova fern, vall’s, riccia, and a fiew other species i cant recall. Problem 1, my anubious and my glosostigma are showing yellowing and my sword is showind deterioration and i have brown hairlike algie and green haire algie. im now adding iron against by better judgement, no changes yet. can anyone help? i know im folowing a fine line or eco balance. i am lacking experience and a lot of expert knolage so be easy on me. p.s. i have 80 galixy rasbora and 10-12 japonica c and i seldom feed Hikari micro pelots. i will try to answer questions asap. 10/12/08
October 13th, 2008 at 7:53 am
John, I’m sorry to hear your algae problems. Your setup sounds very nice, but one ingredient that you haven’t mentioned is whether your fertilize with anything more than iron? If by brown algae, you mean the fuzzy black/brown algae that is very hard to remove and sticks to rocks/wood and old leaves like your anubias and swords, that’s Black Beard Algae. For that, I would recommend using a syringe (like the type you would inject liquid into a turkey), fill it with 3% Hygrogen Peroxide like you can get at the drug store, and squirt it directly on there. That will help weaken it. Only do a few patches each day. Using too much H202 could affect your shrimp. In conjunction, I suspect that your CO2 is far too low. Increase it, watching the fish to make sure it’s not too much.
For the hair algae, if you’re not dosing any nitrates or phosphates, that’s like your issue. Any reason you’re using RO water instead of plain tap? In addition, your plants are likely missing potassium if they’re yellowing. You probably need a full dosing regimen. Read up on dosing. Here’s a good place to start:
http://gwapa.org/wordpress/articles/fertilizing-the-planted-aquarium/
February 20th, 2009 at 10:50 am
great resoursful website. I’m unsure if i have BBA or Hair algae. The algae appeared when my phosphates got super high, but Ive had them between the .1 and .2 mark for a few weeks now. Im running between 3-4 wpg and I think my nitrate levels are low and my iron is low despite dosing. I just got rid of a bunch of plants that were covered in the algae and put new ones in only to have the algae attack them too. I do run a pressurized co2 injection system and my co2 looks good not high but not low. i think im going to try some SAE. How do you inject with H2O2. (tank full or during water change; do i need to remove the plants?)
February 20th, 2009 at 11:03 am
Thanks for the comment, Adam. Black brush (BBA) and hair algae should be pretty easy to tell apart. BBA is black/dark brown with short tufts, which hair algae is green and longer strands/clumps.
If you have low nitrates, that’s likely the source of your problem. Get your nitrates and phosphates in line, with Nitrates between 5-10ppm, and phosphates around 1ppm. You may want to raise your CO2 levels if your fish allow for it. SAE will eat both forms or algae, as do Amano shrimp. If need be, reduce your lighting time period to help get rid of the outbreak.
H2O2 should only be used sparingly, and to treat specific areas with a lot of algae. Use a syringe, like one used in cooking to inject brine into a turkey. Don’t use a lot at once though, as it can hurt the slime coat of your fish, and bother inverts.
April 28th, 2009 at 8:26 pm
yo! hows it going? i had a bad case of brown algae but thank to your advice with the snails and that it takes time. my 55g african cichlid tank is spotless of algae. the snails acctually worked alot quicker than i would have thought.
April 28th, 2009 at 9:01 pm
Glad to hear it, Kevin! Those nerites are priceless.
May 27th, 2009 at 8:03 pm
Hi,
you have a very well organized website, it helps a lot of people… I just have one question. O bought some plantas and now I have come to realize that they brought beard algae, it is black and hairy. I just have a chinese algae eater, do you think it will eat the algae or should I try and get a siamese algae eater?
Thanks!
Regards from Portugal!
May 27th, 2009 at 8:30 pm
Thanks PDH898T, I’m glad you’ve found the site helpful. The name “chinese algae eater” can refer to several different species, but in my experience, they will not eat beard algae. Siamese will, but so will Amano Shrimp. Good luck!
June 6th, 2009 at 3:03 pm
i have a 75 gallon saltwater tank that have black hair algae. how would i get rid of this it is growing all over the bottom of the tank
thanks for any help
June 6th, 2009 at 6:00 pm
Hi Steve. I’m sorry about your algae problem. Unfortunately, I’ve never kept a saltwater aquarium, so I don’t feel qualified offering advice on it. If anyone else see’s this, please feel free to point Steve in the right direction.
August 9th, 2009 at 7:23 am
[...] complete beginner – setting up a 20g High… Guitarfish.org, posts some great information concerning algae with excellent [...]
November 13th, 2009 at 7:03 pm
[...] what I read here and at this link (scroll down a bit) you would definitely benefit from adding more circulation and KNO3. I can tell [...]
November 29th, 2009 at 9:18 am
I have very dark green (almost looks black) stuff coating the edges of my plants, all over my non-live stuff, and in small circles on my glass. Do you know what this is and how I can get rid of it?
November 29th, 2009 at 11:25 am
Stacy, this likely either Blue-Green-Algae (BGA), a cyanobacteria, or Green Spot Algae (GSA). The easiest way to tell is whether or not it is slimy and you can wipe it off with your finger. If it’s slimy, wipes off, and probably has an earthy smell, it’s BGA. If it’s hard and won’t easily scrape off, it’s likely GSA. See the appropriate section above for a number of ways to get of either. Good luck!
December 11th, 2009 at 6:22 am
[...] like it may be blue-green algae (not really an algae but a bacteria). Check out this link Algae in the Planted Aquarium– Guitarfish to see pictures of it and other true algae. The smell of it is a dead give-away. It also shows how [...]
January 14th, 2010 at 12:26 am
[...] Aquarium Plants PlantGeek.net – Plant Guide Plant Profiles – All Plants algae… find and cure… Algae in the Planted Aquarium– Guitarfish James' Planted Tank – Algae Guide Algae in a Planted Tank Algae Common Types – The Planted Tank PG: [...]
January 25th, 2010 at 10:50 pm
I have something similar to fuzz algae only shorter, and all the leaves it covers tend to turn brown and eventually rot away. What is this?! And what can I do other than get a siamese algae eater? (which actually harrassed my cardinal tetras until they all died of stress-related ich =(…)
January 26th, 2010 at 8:11 am
Baka, without seeing it, it’s hard to tell what it is, but most of these algaes are caused by a nutrient imbalance, whether it is unbalance nitrate/phosphate levels or not enough CO2. As an algae crew, Amano shrimp are fantastic and won’t harass your cardinal tetras. Depending on the algae, Otos are also great docile algae eaters.
January 26th, 2010 at 11:51 am
Thanks for replying so fast! I think my nitrates and phosphates are a little high at the moment…oddly enough though, I only noticed the algae appearing when I started adding CO2. I don’t know if that’s a possible cause or just coincidence. Do you think adjusting the nitrate and phosphate levels with more fequent water changes would get rid of that algae or only prevent further growth?
January 26th, 2010 at 11:58 am
It’s not entirely surprising that algae could occur when adding CO2. With CO2, your plants are able to grow faster, consuming more nutrients, which can throw your N and P ratios out of whack. It’s counter-intuitive to the fish-only keeper, but in a planted aquarium, sometimes you need to dose more fertilizers in order to get rid of algae. And yes, frequent water changes are very important to getting rid of algae.