Killing Blue Green Algae a/k/a Cyanobacteria – SFPT009

Art PennomHelp with Algae, Podcast, Pro Tips1 Comment

blue green algae cyanobacteria

Killing Blue Green Algae a/k/a Cyanobacteria – SFPT009

Hello! and happy Wednesday to you! I’m Art Pennom is this is your Wednesday ScapeFu Pro Tip.

Today, it’s about ways to knock out the smelliest of all algaes – it’s blue green algae a/k/a cyanobacteria!

Yes my friends, those of you that have been visited by this nasty, slimy type of algae know what I’m talking about. It’s an ugly bugger. Here’s how to get rid of it.

First, as always, you need to make sure you have all of the positive variables correct. Pay particular attention to organics and the resulting low oxygen levels in the aquarium. When was the last time you cleaned out that canister filter? How about vacuumed that gravel? Do you have enough flow in the aquarium? hmm?

Make sure these things are correct and then try the following to murder this smelly nemesis:

  1. Increase the flow in the areas where you have it. Try it for 1 week. See if that does it.
  2. Hit it with hydrogen peroxide using a syringe. Give that a couple days to work.
  3. Water change and vacuum as much of it as you can. Give that a week.
  4. Erythromycin (Maracyn) treatment. 200 mg/10 gallons.

After all cases, large water changes! Please be careful if you have sensitive fauna in the aquarium.

Try 1-3 above before using the antibiotic. As Diana Walstad tells us in her legenday book, “The home aquarium is an ecosystem; it does not react well to toxins and antibiotics.” Hi, Diana! Hope you’re listening!

Hope this helps those of you dealing with cyano. Let me know if you’ve dealt with this pesky bacteria and how you gave it the ax by leaving a comment in the show notes.

To wrap up, I’m starting a new trend today and closing with a thought on aquascaping for you to reflect on until the next time. And, here it is:

“Every artist was first an amateur.” -Ralph Waldo Emerson

Keep scaping, my friends


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One Comment on “Killing Blue Green Algae a/k/a Cyanobacteria – SFPT009”

  1. steve

    Hi. Was getting cyanobacteria between the leaves of my floating spongeplants / American frogbit until i discovered that by using a wooden kebab skewer to swirl the ugly mess onto i could eliminate the cyanobacteria, ok, only for about a week though, then repeat application of skewer. By the way, i’m having a rough time with black bearded algae and a light dusting of green algae on the surface of my 2mm gravel substrate. Tank is not in direct sunlight, am not overfeeding, tank is not overpopulated, i do a 15% water change twice a week. It’s a 60 gallon tank with vallis, hygrophila polysperma, echinodorus stem plant, direct CO2 injection, pH7. Local tapwater has high phosphate concentrations and i’m at a loss to understand why i’m getting all this algae. Maybe the floating plants need cut back so more light can penetrate the lower plants, maybe i need increased H2O circulation ? Any helpful advice would be appreciated.

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