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Blue-green algae in aquarium – how to get rid of cyanobacteria? | Aquaforest

14 03, 2024

Przepraszamy, ten wpis jest dostępny tylko w języku Amerykański Angielski.

What is cyanobacteria?

Cyanobacteria can effect any marine aquarist. Here is what I have learnt over the years. The experiences I have come across in my own reef aquariums and working in the marine aquarium industry 

What causes cyanobacteria to appear in an aquarium? 

Cyanobacteria can be caused by a number of different factors such as excess dissolved organic material. That ends up as detritus in dead areas of you aquarium. The bacteria needs phosphate and nitrate to survive. These levels can become high is you are over feeding or waste is not being removed by filtration.  

All algae need phosphate to thrive so this would be the first thing I would look at resolving. It could be something simple like your water source from a RODI unit not having the filters changed enough or just detritus sat around the aquarium. 

The main reason in my experience to having cyanobacteria is high Lighting with to much white light and not enough flow or to many dead spots in the aquarium that don’t get enough water movement allowing organic waste to sit and break down.  

How to identify cyanobacteria?  

In some cases I have seen it so bad that it looks like a bright red carpet on the sand bed and other times I have seen it just dotted across rock work. 

The first signs are blue or green coloured crust along the shoreline, thick puffy blue or green foams on the surface of the water looking like protein skim, or swirling colours beneath the surface of the water. Blooms can sometimes be white, brown, or red in colour 

How do you get rid of cyanobacteria?

In most cases, some vacuum cleaning and a portion of good bacteria will already help to solve the problem. Cyanobacteria will be gone in a week or so. 

If you are having trouble removing the cyanobacteria I use a simple method that has always work for myself and many other reefers I have helped in the hobby.  

  1. firstly I syphon the bulk of the cyanobacteria and detritus out.
  2. I would then reduce the light intensity or how long the lights are on for in the day. 
  3. I would then increase the flow in the tank. If that’s turning the return pump up or moving wave makers into a different location in the aquarium.  

It can feel like a loosing battle at times but it can take time for your aquarium to become stable and the cyanobacteria to go or die off. 

I hope this help anyone have cyanobacteria problems. 

Thanks Mini_Reefin

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