THoughts on cyanobacteria

asylumdown · #1 04-13-2013, 10:46 PM

I've always thought there was something more going on with cyanobacteria than the common forum wisdom about algae has let on. Namely, it's because I've seen every single probable cause and remedy for it stated as though it's a fact - cyano thrives in low nutrient tanks, cyano is a sign of excess nutrients, cyano thrives when one nutrient is depleted relative to the other, cyano only occurs in low flow, cyano can occur anywhere, etc. etc. etc. Every single aquarium 'case' has at one point been blamed for cyano, even mutually exclusive cases. Also, other than chemical treatments like chemi-clean, there's not really an easy way to knock it out once it starts growing. I've seen cyano at some point in just about every tank I've seen in person, or seen pictures of online, regardless of the husbandry practice. True some tanks get it worse than others, and I lean towards thinking that high nutrients in general help it get out of control, but something about it has never really added up to me. I got really interested in it when I had a massive cyano explosion in my first tank upon adding biopellets, because so far, no one's been able to offer a good explanation as to why that happens. The best explanation I've seen is that since cyano is a bacteria and not a true algae, it's somehow able to capitalize on the sloughed off carbon polymers that make it in to the water column.

In any case, I have a small patch that started in the corner of my tank that's been slowly expanding for a couple of weeks. My tank is pretty darn close to ULN status, and no other algae really grows in my tank, and yet, day after day, the patch of cyano is advancing up the glass. It's the red wine coloured, slimy mat forming kind that I'm sure just about everyone has seen before.

Since I have a microscope now, I decided to look at it under magnification. I took two samples, one I pulverized in some tank water so that it was just reddish coloured water, and the other that I put on a slide relatively intact. The pulverized sample showed me exactly what the internet told me to expect, long strands of single cell chains of garden variety cyanobacteria. It was the intact sample that was really interesting. At low magnification, the cyano formed a tight weave that looked like a basket, but it was throbbing, almost like it had a pulse. At higher magnification, it was clear that was was causing the movement was thousands upon thousands of some other species of bacteria (diatoms maybe?) that were sliding in/amongst/through the threads of cyano. There were also much larger (but still invisible to the naked eye) worms actively sliding along, and a few spots of what appeared to be highly motile dinoflagellates.

I took a short video, hopefully it displays on the forum properly:

I edited it for the highlights. As you can see, the motile single cell organisms (bacteria? diatoms?) are almost as numerous as the strands of cyano, and they were pervasive and evenly spaced throughout the entire sample. All in all, the piece of 'cyano' that's presently in my tank is actually a living conglomeration of 4 distinct species of micro-organism, with cyano really only being the scaffold upon which the others seem to live.

I've looked at my sand, rock scrapings, tank water, dino outbreaks and all number of bio-films and slimes under my microscope, and I've never seen what appears to be such an intentional and consistent assemblage of organisms all living together. I tried doing a cursory search of 'cyano ecology' online and didn't find anything (there might be something and I just haven't found it), but from what I saw, to me it's starting to look as though the mats of 'cyano' that we can see at the macro scale in our tanks are actually a lot more complex than a simple blue-green algae. I have no idea how the things that make up the mat in my tank influence each other, who's eating who, or if there really is a relationship beyond the cyano providing an ideal substrate, but if there is some sort of synergistic relationship between the cyano and the things that live in it, I wonder if that might explain why cyano 'outbreaks' seem so baffling in some cases. Just like how a forest can set up enough feedback loops that it can begin to create the conditions necessary for it to spread, I'm wondering if the relationships between the cyanobacteria and it's commensal organisms are actually working together to support the development of the entire colony (which is that mat that we see) thus making their little 'forest' much more resilient in a broader range of environmental conditions.

Depending on what you guys think I might post this in the advanced topics section on Reef Central and see if anyone who's studied this more closely thinks there's anything to it.

Delphinus · #2 04-13-2013, 11:07 PM

Wow, cool. Cool observation and awesome video. What are you using for a microscope and how do you capture video through it?

brotherd · #3 04-13-2013, 11:23 PM

That is very cool.And I don't want any.I'm sure there are more than a few on rc that would like to see that too.

asylumdown · #4 04-13-2013, 11:24 PM

I'm using an Omax with 4 stages (4x, 10x, 40x and 100x) that came with digital USB camera you can put in to one of the eye pieces. I took the video at 40x

daniella3d · #5 04-14-2013, 12:20 AM

Very interesting video. I don't know if those diatoms have anything to do with the cyano but I would bet they are just living in the same type of environment that has beneficial conditions for both.

I had cyano growing in my tank and after getting my new skimmer it all went away in less than a week. No more cyano, gone, totally.

I think the most important factor for cyanobacteria to thrive is dissolved organics (DOC). Even if you have low nitrates and low phosphates you still can have cyano if you have any DOC in the water. I don't think there is a way to mesure the amount of DOC In the water...maybe with an ORP probe? not sure.

My new skimmer is pulling the same amount of skimmate in one day that the other was pulling in weeks. So now my water is deprived of DOC and the cyano simply died. I beleive that if someone has a cyanobacteria problem then it probably is due to the skimmer not being efficient enough for the bioload. In my case it could be a coincidence but I have not change anything else and my nitrates and phosphates are still quite high, so that's not it either.

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http://netclub.athiel.com/cyano/cyanos2.htm

Any of the conditions that adds organic compounds to the water exists in your situation and probably more than one is at work, not just a single one. When water chemistry gets out of hand, the causes are more often than not, multiple.
The skimmer removes "some" of this dissolved organic material but more is actually produced than the skimmer is removing. This is a very common occurance. Either the load is high or the skimmer too small, or both. In either case, DOC will start to build up.
Given enough time, the amount of dissolved organic material reaches a stage and a concentration where the amount present starts giving rise to the appearance of red slime algae because there are now enough nutrients present to allow this growth to occur. In this respect you may wish to consult "Organic Chemicals in Waters" James W. Moore and S. Ramamoorthy, Springer Verlag, 1984, ISBN 0-387-96034-1 (cost $50.00).
When the increase continues more and more cyanos will grow since what is being removed is less than what is added to the tank water.
This accounts for the growth that seems to rapidly increase once it takes off even though you may be siphoning algae out and changing water.
It should be noted that the slime produced by these cyanobacteria is just about pure organic material and decomposes, adding more organic matter to the tank.
Of course the amount that decomposes is replaced by a new sheath of slime, and the process just continuous on and on. One dies off and decomposes, adds organics to the water, and immediately a new one develops underneath (and at the same time) that soon dies and adds more organics, a new one grows, etc. You get the picture. DOC keeps rising and rising.
Organics are not the only matter involved in the growth of blue-green algae (Cyanobacteria or red slime or whatever else you want to call it actually). Iron is another nutrient, but to a lesser degree than DOC or dissolved organic carbon (organic material dissolved in the water). I mentioned an interesting book earlier. Another easier one that you may wish to read or perhaps refer to if you can find it at a library is: "Inorganic, Organic and Biological Chemistry" by Philip S. Chen, Second Ed., The Barnes and Noble Outline Series, 1979. ISBN 0-06-460182-x (originally published by Harper and Row).
Those of you who have dealt with red and other slime algae have gone through this and know exactly what I am talking about.
Once the growth of red slime algae starts, rapid intervention is necessary or the whole tank will soon be covered with them and the growths will choke what is underneath, often killing life forms. Life forms that die off then lead to more decomposition and more organic matter being added to the water.

In essence, what I have found is that when the amount of dissolved organic matter builds up to a high level, sooner or later (usually sooner than later) red slime or blue-green algae will start to grow.
The key then, is to keep this amount low. This is achieved through skimming but may need to be supplemented by other means, especially if you have red slime algae present in the tank already.

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Cal_stir · #6 04-14-2013, 01:00 AM

Great video, I think your on to something here, I think cyano is way more opportunistic than we know, it defies logic and everything we think we know about it. Sometimes it doesn't matter how diligent we are with our husbandry and nutrient control and cyano still rears its ugly head.

Zoaelite · #7 04-14-2013, 01:08 AM

For some reason your posts always seem to get me searching through mad PDF files

, especially when I should be studying for my finals.

I found a paper detailing Cyanobacterial aggregates in the Adriatic Sea that might reveal some answers for you. Unfortunately you can only view it through the academic MRU search. Here's the citation, if you can't access it through the fancy UoC PhD resources you covet shoot me a PM and I will give you my log in information.

Quote:

PUŠKARIĆ S. Ecology of gel-like marine snow event in the northern Adriatic Sea. Acta Adriatica [serial online]. December 15, 2012;53(3):375-387. Available from: Academic Search Complete, Ipswich, MA. Accessed April 13, 2013.

Here's a couple exerts from it, possibly identifying what those additional microbes are in addition to information about its growth.

I think you might be onto something here Adam, keep up the good work!