Bye Cyanobacteria!

[sixty_reefer]

I found this video on journey to the microcosmos on YouTube.



1:08

And the ones I’ve been seeing in my tank

I’ve also noticed that not all amoebas have the same feeding strategy. Vampyrellids are a good example, as some don’t simply engulf their prey but instead pierce the cells and extract their contents.

 

[Lasse]

I must say that its not total impossible that sixty reefer is right in one claim - something is eating his cyanobacteria - the question I see - what?

I think that both me and many others may have fallen in the rabbit hole of only chemical parameters and/or competition plays a role - like the old discussion of micro algae growth only was a result of the availability of nutrients and/or lack of competition instead of the lack of grazing pressure.

If we add grazing to the picture around the cyanobacteria problem we may have some understanding why it can suddenly disappear without any known reason.

It happens in my own aquaria - after years of patches of a dark read cyanobacteria mats - they suddenly disappear except for some isolated parts just below the water surface. I´m sure - there is still this type of cyanobacteria in the aquarium - but they do not form mats.

I still do not think that lack of grazing is the reason why the formation of the mats start This is due to the availability of cyanobacteria as food determining the size of the grazers' biomass and the doubling time of biomass (up to a certain size) may be shorter for cyanobacteria compared to possible grazers. (production is greater than consumption) - but it could be a a possible explanation why they suddenly - without any obvious reason - disappear.

This may explain that disturbing the mats can be effective because it removes a lot of the energy for the mat-forming cyanobacteria. The jelly-like substances that form the mat itself are most likely external storage of sugar from photosynthesis - the production of slows down due to lack of energy while consumption increases or remains at the same level. Note that I am not saying that it is this way - just that it may be a possible explanatory model.

Sincerely Lasse

 

[sixty_reefer]

I’d just like to add that Cyanobacteria may not be the only thing they’re eating. In this sample, they also appear to contain the single celled algae that grows on the glass in my aquarium.

 

[Lasse]

And the ones I’ve been seeing in my tank

IMO - this two pictures is not even in the same universum. The last one seems to have a mouth and the extension could be cilia.

And the pictures you have take clearly shows that the organism has a mouth

If you can take a video how your organism move - when it could be easier to determinate what it is.

I’ve also noticed that not all amoebas have the same feeding strategy. Vampyrellids are a good example, as some don’t simply engulf their prey but instead pierce the cells and extract their contents.

You do not give up! Where in your pictures can you show this behaviour from the organisms in your aquarium?


Sincerely Lasse

 

[sixty_reefer]

IMO - this two pictures is not even in the same universum. The last one seems to have a mouth and the extension could be cilia.

And the pictures you have take clearly shows that the organism has a mouth

If you can take a video how your organism move - when it could be easier to determinate what it is.



You do not give up! Where in your pictures can you show this behaviour from the organisms in your aquarium?


Sincerely Lasse

I agree it does looks like to have a mouth.

Amoeba = shape shifting

But if not enough this video of it moving should help

 

[Lasse]

But is they the same organisms that you have shown with cyanobacteria inside?

I would say - NO

I have no doubt that you have amoeba in your aquarium - but are those with cyanobacteria inside and with a mouth amoeba? I would say no

Sincerely Lasse

 

[sixty_reefer]

But is they the same organisms that you have shown with cyanobacteria inside?

I would say - NO

I have no doubt that you have amoeba in your aquarium - but are those with cyanobacteria inside and with a mouth amoeba? I would say no

Sincerely Lasse

They all have different shapes as shown in the long video last night.



They all appear to have a mouth and “fake legs”

As in this picture

Some more examples

 

[sixty_reefer]

Yellow “fake legs” red “mouth” ?

 

[Dan_P]

Here is the eating process of an amobae type of organism

https://av.tib.eu/media/21957

Sincerely Lasse

Thanks Lasse. Unfortunately, my iPad couldn’t find the server.

 

[Lasse]

Thanks Lasse. Unfortunately, my iPad couldn’t find the server.

I have tested (VPN) from two locations in the US - Chicago and Denver - and its no problem to reach the web site

https://av.tib.eu/media/21957

Sincerely Lasse

 

[Lasse]

Yellow “fake legs” red “mouth” ?

IMO

Orange - probably a flagell or a cilia
Red - looks like a mouth to me

Sincerely Lasse

 

[EnterName]

This is a poor quality video. Why don’t you just concentrate on finding a high quality example of an amoeba engulfing a filament, showing the process by which it severs the filament?

Here is the eating process of an amobae type of organism

https://av.tib.eu/media/21957

Sincerely Lasse

I've gone through their videos. They have a few on amoebas with quite interesting information on what they do, and how they do it, but you already have to know a lot of terminology to understand everything.

They have a video comparing how different amoebas ingest different organisms: https://av.tib.eu/media/11080

Some detect being touched by ciliates and start expanding their pseudopoda in that direction to enclose them. Others simply "roll over" diatoms or smaller bacteria.

But cyano filaments are quite large so I had to dig a bit deeper. Unfortunately the sources seem limited to freshwater this doesn't seem to be observed much in marine environments, so take it with a grain of salt (pun intended): Most amoebas that eat cyano filaments coil them up to make them fit into food vacuoles. This obviously has it's limitations but if the filament isn't too large and the amoeba of decent size this works fine. Some ciliates do the same but they can "bite off" pieces if the filament is too large. There also was an interesting video on that where it showed how enzymes are directly moved to the mouth opening to directly soften the filament to make it fit and bend inside the cilliate's body: https://av.tib.eu/media/21955

There are a few amoebas that can "bite off" chunks as well, but this seems to be more rare. I have not found any data on wether they prefer to eat in small chunks or just bite off once they can't fit anymore into their body.

Some amoebas also start eating from the middle of a filament and bend it, but I didn't look much further yet.

Edit: I have not checked all the new posts yet so I don't know if those things are amoebas, ciliates, or something else.

 

[sixty_reefer]

Just an entertainment video for the time being an amoeba like organism hunting diatoms. The video has been sped up 5x.

 

[Dan_P]

I have tested (VPN) from two locations in the US - Chicago and Denver - and its no problem to reach the web site

https://av.tib.eu/media/21957

Sincerely Lasse

Still doesn’t work

 

[Dan_P]

I've gone through their videos. They have a few on amoebas with quite interesting information on what they do, and how they do it, but you already have to know a lot of terminology to understand everything.

They have a video comparing how different amoebas ingest different organisms: https://av.tib.eu/media/11080

Some detect being touched by ciliates and start expanding their pseudopoda in that direction to enclose them. Others simply "roll over" diatoms or smaller bacteria.

But cyano filaments are quite large so I had to dig a bit deeper. Unfortunately the sources seem limited to freshwater this doesn't seem to be observed much in marine environments, so take it with a grain of salt (pun intended): Most amoebas that eat cyano filaments coil them up to make them fit into food vacuoles. This obviously has it's limitations but if the filament isn't too large and the amoeba of decent size this works fine. Some ciliates do the same but they can "bite off" pieces if the filament is too large. There also was an interesting video on that where it showed how enzymes are directly moved to the mouth opening to directly soften the filament to make it fit and bend inside the cilliate's body: https://av.tib.eu/media/21955

There are a few amoebas that can "bite off" chunks as well, but this seems to be more rare. I have not found any data on wether they prefer to eat in small chunks or just bite off once they can't fit anymore into their body.

Some amoebas also start eating from the middle of a filament and bend it, but I didn't look much further yet.

Edit: I have not checked all the new posts yet so I don't know if those things are amoebas, ciliates, or something else.

Thanks for this review. I venture to speculate that amoeba are not a significant threat to a cyanobacteria film.

 

[RobertK]

Just an entertainment video for the time being an amoeba like organism hunting diatoms. The video has been sped up 5x.

Is it hunting diatoms or just squirming around next to one? Did it go on to engulf the diatom?

 

[Lasse]

I have not checked all the new posts yet so I don't know if those things are amoebas, ciliates, or something else.

Neither do I but I have to give @sixty_reefer an excuse because in my digging I have found the article attached in this post. Its a rather late article (2023) and it cover an experiment to feed freshwater amoebas with the Oscillatoriales from the genus of Oscillatoria. Its freshwater but the microscopic photos are rather alike the photos from sixty reefer. I do not publish the photos - they are in the article - read it.

However - I will made a comment about this thread. Sixty_reefer claimed it was amoebas from the beginning. Lot of people - including me - ask for evidence for this claim. To be honest - there was no evidences reported by Sixty-reefer - only the claim. The thread get rather rough and Sixty_reefer state this

This is exactly what I meant by crowd reinforcement. The focus seems to be on finding something wrong with the observation rather than working together to understand what is actually being observed.

Now it turns out that one of the opponents has dug up an article that can indicate that it could be amoebas you see in your samples. However, I want to strongly point out that I have not found any evidence that marine amoebas can eat in this way. In the study I found, over 20 species were tested but only 3 managed to survive on filamentous cyanobacteria.

Sincerely Lasse

 

[Lasse]

@sixty_reefer - I must ask you this question because its green cyanobacteria you work with - is this experiment in saltwater or freshwater?

Sincerely Lasse

 

[sixty_reefer]

Is it hunting diatoms or just squirming around next to one? Did it go on to engulf the diatom?

There are three different algal targets being hunted in this video. The red circle is a diatom and it gets engulfed in the video. The blue circle is another type of diatom but I’m not sure how it ended for him as my phone ran out of memory and I was trying to sort it out. The yellow circle is possibly an algal zoospore and that also gets engulfed in the video.

 

[sixty_reefer]

@sixty_reefer - I must ask you this question because its green cyanobacteria you work with - is this experiment in saltwater or freshwater?

Sincerely Lasse

Saltwater