Aquarium Algae

Did you know that some Aquarium algae doesn't just look terrible, it will kill your fish.
Did you know that some fish need algae to supplement their diets?
Learn all this and more, and let us help you find the cause, and the cures for the different types of algae problems you might have.

Aquarium AlgaeAquarium Algae

Different Types of Aquarium Algae

There are many types of algae and the list could be much longer, however, here are the most common culprits that can get out of control, some of the causes of them, and some easy cures for them.

  • Brown Algae
  • Green Hair Algae
  • Brush Algae
  • Blue Green Algae
  • Green Spot Algae

First let me suggest that whether you have a tropical or freshwater tank, your first step is to purchase an Aquarium Algae scraper regardless. It will become a handy tool to expedite any problems quickly. It is a magnetic device that allow you to easily remove the algae from the inside of the glass tank, without having to get your hands wet.  My favorite is the Marina Magnetic Algae Scrubber.

If this leaves you still wanting more fish to help with your algae problem, keep reading. If you are thinking about snails, we will tell you more about those later too.

Goldfish TanksGoldfish Tank Health

The type of fish you have in your tank, will always be a factor of algae problems. For instance, the Goldfish produce lots of waste, which is lots of phosphates and nitrates, which when mixed with sunlight, creates algae growth. This is also the type of algae that will kill your other fish and plants.

Another example with the Goldfish (and some other species) is they will actually kill themselves overeating (producing all the waste), and what they don't eat falls to the bottom to rot in the substrate. 

Over feeding creates waste, and leads to not only algae, but bacteria and illnesses for your fish.

There may be too much or too little light, or sunlight for the tank you have, so consider using a timer for your aquarium lighting and fish needs. Using aquarium light for more than six hours a day can cause excessive algae growth. Learn more about Tank lighting here.

Your PH levels are not appropriate for the acidity or alkalinity of the Salt water or Fresh water tank you have. 

If your Water quality is beyond help, I suggest changing at least 10% of it every week for a while, then on a monthly basis until your tank matures.

Learn more about Marine Tank Health here.

The other side of the coin is the Angel fish who loves to eat, and thrives on vegetation. It not only filters and cleans the tank water of decomposed materials, it reduces aquarium algae. Learn more about the Amazing Angel Fish here.

Common Characteristics of Aquarium Algae

Brown Algae

    The most common type of algae found in aquariums is Brown algae. It may first appear as a fluffy or spotty appearance on glass, rocks, substrate, plant leaves,  and decorations. Brown algae grows more rapidly in low light. If brown algae happens in a well established tank, check all water conditions, and lighting again. 

    Possible Causes and Solutions:

  • Low light- replace old light bulbs.
  • High nitrates or phosphate levels-replace with a new filter and clean it often.

  • Poor water quality-conduct regular water changes.

Green Hair Algae

Another common type is Green Hair algae. It can look bushy, with or without spots, and grow in clumps. It is light green, and can grow to over an inch long if left unchecked.

Possible Causes and Solutions:

  • High light-reduce lighting or time of it.

  • Low c02- increase c02 levels.
  • Low nitrates-increase nitrate levels.

Brush Algae (Black or Red)

You will find Brush algae growing on the edges of the leaves, bog wood, around your filters, and usually in clumps of black or red tufts. leaf edges of slow growing plants, bog wood and around filters etc. Grows in clumps or patches of fine black or red tufts up to about 5 millimeters long.

Possible Causes and Solutions:

  • Low or fluctuating frequently CO2 levels-Increase the levels of CO2 levels for your tank. Increase water circulation and especially around the plants.

  • Low Light Tanks need to reduce water changes to see if this helps.

Blue Green Algae

Blue Green Algae is not a real algae at all, but a bacteria. It will cover everything with a blue-green sheet of smelly slime. It can be peeled off, but grows back rapidly. Easily peels off but grows back again very quickly. Most commonly if you look where the top of the substrate meets the found glass you will see it first.

Possible Causes and Solutions:

  • Low nitrates or high levels of other nutrients-Improve the water quality and circulation. Stir the water to loosen the substrate and mix up the water. Improving water circulation reduces this algae.

  • Dirty substrates and filters-clean or buy new substrates and a new filter. Vacumn the substrate at every water change.

  • Too much light-do a 'black out' and cover the tank for a week or so.

  • As a last resort you can use erythromycin. However this will also kill the good bacteria, so use with care.

Green Spot Algae

Forms hard green circular spots on the glass and plant leaves.

Possible Causes and Solutions:

  • Low c02-Check CO2 levels

  • Low p04 levels (phosphate)-Check P04 levels, and make sure you are not overfeeding.

  • Too much light-reduce time light is on between 8-12 hours. Using a timer is a great helper.

Depending on the type of aquarium algae you have a problem with, will also determine how you can effectively treat it. But remember, Algae scrapers are great to remove any traces of algae.

Do you have specific issues or problems with your aquarium?  Ask it here, and we will help you. If you have pictures, upload them so we can pinpoint your issue easier, and have the best answer possible for you.

Got a particular question or problem we can help with?

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