Anyone have experience with culturing these things? I find them fascinating. Biologists seem to be more experienced with cultivating single-strain algae on agar and then propagating them from there.
But this means the complex interactions between cyanobacteria, diatoms, algae, sulfurous bacteria etc never get documented formally. The best I've been able to find are field excursions reports in salt marshes.
>>2310524
like most marine aquarists I'm great at culturing these things.
we try really hard to get rid of them, that's probably why they're so easy to grow.
anyways all you need is a saltwater tank with reef lighting, no filtration, poor water movement, a deep sandbed, tons of nutrients, warm water, and a long photoperiod. They pretty much grow themselves.
Bump for interest
>>2310537
would it be self sustaining? Or would you need some rotten fish or something in there too?
>>2311701
self sustaining. I had a batch of cyanobacteria and diatoms that covered a tank for 4 years straight. All I fed them is RO/DI water to top off evaporation.
I assume they die off and then new cells feed on the dead. As long as you don't have anything eating them they'll hang out forever I'd guess.
>>2310537
There's a difference between biofilms established by traveling microalgae and full microbial mat ecologies. Biofilms are ubiquitous worldwide (the surface of your teeth and intestinal tract are the closest examples you will find) and cultivating a simple biofilm is as easy as turning on the outdoor faucet and waiting for the soil to green. These simple associations tend to become host for bryophyte spores in my experience and I've read some evidence they are symbiotic.
Complex microbial mat ecologies are rarer and typically only grow in environments free of bioturbation like the bottom of Lake Untersee or Lake Vanda in Antarctica, Shark Bay in Australia, or Sippewissett Salt Marsh. These mats grow to several centimeters thick and accrete complex stromatolites over (enormous lengths of) time like pic related.
These represent the first ecologies of life on the bottom of the ocean, before the Cambrian Substrate Revolution, and the first ecologies of life on land, before the rise of even primitive non-vascular plants like liverworts (for two billion years Earth's terrestrial surface was dominated by mat ground ecology and this is nothing but a passing footnote in most paleontology textbooks). This is what the world looked before even basic arthropods, chordates, or plants and very likely provided the basis for all that came after.
Mostly I'm just looking for people with experience in culturing Winogradsky columns.
>>2311749
sorry, I supposed from your picture you were interested in marine stromatolite cultivation which is no more difficult than I mentioned.
all you need is some occasional stirring of the anoxic deep sand bed to get sand trapped in cyanobacteria. Anoxia in the sand bed produces the necessary hydrogen sulphide to support all sorts of interesting bacteria. Cyanobacteria serve to calcify the sand in place forming concretions over a period of some years.
I'm sure your freshwater stuff is interesting, but I've only had experience with the stuff in the OP pic which is an extremely common phenomenon in reef tanks with anoxic sand beds and high nutrient levels.
>>2311749
>this is nothing but a passing footnote in most paleontology textbooks
it received considerably more than a passing mention in recent works on the Permian extinction event and the Paleocene–Eocene Thermal Maximum (PETM).