What is the actual cause of Cyanobacteria ?

[Tom.E]

It’s 2021 nearly 2022 and yet I’m still unable to find a definitive answer on what causes a Cyanobacteria many answers on the web include….

Low flow
Low nitrate
High phosphate
Low phosphate
High dissolved organics
Redfield ratio
Carbon dosing
Detritus
Introduced from another system
Lack of bio diversity
Over feeding coral foods/aminos
Low oxygen

And the list goes on and on

surely there is an exact cause which attributes towards a cyano bloom feel free to chime in……

reef keeping has become so advanced but yet the same old info above is battered back and forth

From what I know and read, various species of cyanobacteria can utilize dissolved organic nitrogen when dissolved inorganic nitrogen is low or absent. This may be one reason why cyano blooms occur in established tanks that zero out in NO3. FW planted tanks that reguraly dose KNO3 usually don't have issues with cyano.

With newly set up SW and FW water tanks, cyano is one of the faster growing pioneer species when it comes to competition for substrate. NH4 may play an important part.

IMO and IME

Tom

 

[Randy Holmes-Farley]

Along the lines of Dan’s discussion of silicate for diatoms, we can take a similar look at cyano.

Like all photosynthetic organisms, cyano need a long list of things, including some source of many different elements, to thrive. In general, these are similar to the needs of corals, but there are some differences.

There are three special things about cyano:

1. Many species can use N2 from the air as a source of N, although no one has ever shown that problem cyano in a reef tank are actually getting a lot of N this way. Cyano alone will never do better at low nitrate than at higher levels, but it might be better able to deal with a shortage of available N than competitors for space such as green algae.

2. Cyano can readily metabolize organics and may even grow in the dark if enough organics are present. So higher organics might give them an edge.

3. Being bacteria, cyano may be better able to survive in low iron situations than some competitors, due to their ability to use siderophores to go out and scavenge iron. Thus, keeping trace elements higher may spur competitors to cyano.

 

[DE FISH]

Keep it going guys

 

[metalle]

The varying causes of Cyanobacteria may be due to the organism itself and the different Cyanobacterium that could be present in a system. If I remember correctly, not all Cyanobacteria are the same. While they are phototrophs, some can use CO2 for its carbon needs, & others need organic carbon. Some use inorganic phosphate, some can use the phosphate bound in an organic compounds, and others can use the phosphate bound to the substrate. If this is true, it would be impossible to find one cause.

How can you identify which bacteria is in your system? Is there a method?
Thanks
G

 

[ReefGeezer]

How can you identify which bacteria is in your system? Is there a method?
Thanks
G

I am afraid the answer to that is over my head. I suppose my post was way too generalized. When speaking about cyanobacteria, I was including all, not jus the ones that cause the red mat in our reef tank. To be more specific, I think the Cyanobacteria that cause that sort of problem have more specific requirements. Those requirements include available light and dissolved organic carbon to fuel its photosynthesis process and nutrients to build its biomass.

 

[bushdoc]

I second Dan_P explanation.
There is something called succession in Ecology and our tanks are part of nature, whether you want it or not. Immature systems are more prone to various imbalances as Cyanobacteria and Dinos are opportunistic organisms evolved to colonize substrate or environment unsuitable to other organisms. Cyano and Dinos can bloom though even in totally mature environment. I saw it while diving in Fiji, when House Reef was polluted by fertilizer from the Island.