The Slime Mould Collective

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I was able to get some physarum sclerotium from a biological supply store. It came in a glass vial on some filter paper. I followed the directions as the included paper said: moist paper towel in plastic container in a dark place, place oats near it and rinse with distilled water daily.
It has been 3 days and all I can see is a clear gel/slime substance on the filter paper. Is this the slime mold? It is not yellow and has not moved or began fanning out to find food.
What am I doing wrong?

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I have ordered some sclerotium and it will arrive by mail in the next few days.
So, I have been searching a bit on the web and I can't directly find pictures of sclerotia and young slime molds. It clearly isn't a popular hobby yet.
When it arrives, I will attempt to document my experiences in detail.

I can't help out yet, but I have seen pictures of nearly bleak/transparent slime molds that could be Physarium.
If your slime mold turns out alright in the meantime, please tell so, so that I don't get anxious when I see the same symptoms.

Good luck!

Well, the slime mold has taken hold and is beginning to grow. Hopefully I can propagate enough to shar with anyone who needs it.

Good to hear!
My sclerotia have arrived today. The instructions that came with it suggested to start with oatmeal agar.
So, I hope I'll have some growing soon!

Glad to hear it came back to life. Eventually! Feed it up well for a few days before doing any experiments, it should perform better. Enjoy!

To be honest, the sclerotium look like dried crumbs of yellow/orange bread. At least from my source.

Hey, I want to give an update about my experience.

So, i received the Physarium P. sclerotium from Scientio with the instructions to grow them on some oatmeal agar (200 ml water + 12 g oatmeal (I just put some oatmeals in a coffee grinder) + 3 g Agar)

And I thought, let's start with 2 small pieces to see how everything works. I placed them in 2 Tupperware pots and after about 2 hours, It became clear that it started getting alive (unlike the 12-24 hours as said in the instructions).  Then during the night it grew in both Tupperware pots that it covered the entire agar bottom. (while I thought it would still be in the process of waking up) And now it is like a vainy surface, I upladed a picture)

I transfered a tiny piece onto some oatmeals on just a piece of wet paper in an other box and indeed that indeed seems to grow much slower.

So, if you find that your slime mould is not growing, placing it on oatmeal agar will probably do the trick.

In the next days, I'll see if I can return it back to a sclerotium.

Wow! Excellent growth!
I guess I'd better get out the agar.
Did you add the oatmeal into the agar or just make a broth out of it and strained the oats out?
I would like to try that method of culture.
Mine started growing pretty well but nothing like yours. Although I have managed to propagate chunks of it and I now have 10x the amount I originally had.
What I really think would be interesting is to see if physarum can be grown in a nutritious liquid(oatmeal broth?). My hypothesis is that the swarming cells would swim through the liquid and multiply at a rapid pace. Then after the jar became thick yellow with cells the excess water could be strained out and you could have a massive chunk of plasmodium to experiment with.
Do you think it is possible? I'm certainly going to try.
Keep those agar pics coming. That slime mold looks great!

I just added the agar and oatmeal to the water and stirred till it boiled.
Then I poured the liquid in some containers where it cooled and solidified.

I don't know about the liquid form, I think the Physarium must be able to breath.

Also, I have now (2 days ago) filled the bottom of an aquarium with agar (without the oatmeal). Placed a map (of Belgium) under the bottom glass and placed some oatmeals on the respective positions of some major cities to see if it will replicate the highway network.
It now grows in a nice network way instead of the solid surface way when oatmeal is added to the agar)

And I'm slowly drying out the oatmeal agar to see if I can obtain sclerotium. But It looks as if it is going to fruit.

I followed that oatmeal agar recipe but I did not grind up the oatmeal. It still turned out well, but a little chunky:).
It has been about 8hrs since I placed some colonized oat flakes on the agar and just as u said, growth is explosive. Each piece already has dime size diameter of hunting plasmodium and when I get home from work I'm sure the agar will be nearly covered:).
Also, I think I read somewhere that slime mold eats bacteria that grow on decaying things. In nature this would be logs, leaves, soil etc...
But in our case the bacteria is grown on oats or agar. And when we make agar we have to use some form of heat to melt the agar to mix it with water and perhaps this kills a lot of the bacteria.
While letting the agar cool and in the process of placing sclerotium or plasmodium on the surface, it is exposed to the open air and bacteria begin to grow. But the slime mold quickly covers the surface eating all the bacteria. This is all just hypothesis, but maybe there is no food left on the agar and this is why yours is fruiting instead on making sclerotium.
According to this:,
Starvation=sporangia and dehydration+food= sclerotium.

Once my agar is covered with physarum I will also try to produce sclerotium, but I am going to add some extra oat flakes to the surface first to test my hypothesis.

It hasn't fruited yet, and I think it has plenty of food, the agar is moist, so nutrients from the oatmeal will probably diffuse to the slime mold.

It looks like it is doing something like this:


It reaches up in the sky. And the next morning, I saw that it grew up along the sides searching for an exit trough the plastic foil.
I'm starting to look around to set up some time lapse rig. 

This thing grows so fast. I've read about people calling it a pet, I thought that it was some way of speech like you have people having a 'pet rock'  or a 'pet plant'.  But it kind of actually is a pet, isn't it? At least the same pet level as a snail or something.

A time lapse would be awesome.

And yeah. I can see how some people could think of it as a pet. It needs food, water and care. It is a great disposable "pet" to teach children responisbility. And they seem to be pretty resilient to mistakes.


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