Culturing Infusoria

[MickS77]

I'm looking to keep some infusoria for raising tetra fry. Anyone keep infusoria? What do your setups look like and do have any tips or tricks?

[Wmarian]

Good question. Here is my approach, I just don't know if I am "really" raising such a culture or not...do we have a technical definition of infusoria? And what would we say is technical difference from green water (also useful for tiny fry?)

 

I have only small set of fry, so my set ups are small.

Infusoria: I started by setting water outside for two weeks. Moved it inside in to a half gallon clear plastic container, keep it on the windowsill with pretty bright indirect light, uncovered. Throw in a dandelion leaf, piece of banana peel, lettuce leaf or slice of zucchini (etc.) about once every week or two (once the previous leaf/food source is almost mulm). I can see lots  and lots of critters zinging around in there when I hold a light to it. Use a turkey baster to clean out about a cup of mulm/waste at the bottom every week or two, and top off with aquarium water.

Green water: Then I also took half of that infusoria mix into another container and topped off with aquarium water. Added a handful of grass clippings and fertilized heavily with Easy green. Keep on a windowsill with a few hours of direct sunlight, and got green water eventually. So far have just been feeding this with Easy green. So this has both floating algae and little critters zinging around in it.

Looking forward to seeing other answers/tips

Edited July 22, 2020 by Wmarian

[Daniel]

I grow larger infusoria (metazoans), like seed shrimp in this tank. I feed it kitchen scraps, leaves and mulm.

Those are seed shrimp eating a piece of squash below.

For the true infusoria (protozoans) I grow green water in 5 gallon buckets outside (squirt of Easy Green and sunlight makes green water) and then feed the green water to these containers.

You can also get instant infusoria by squeezing the grunge out of a sponge filter. And plants like java moss are covered with all kinds of microscopic critters.

Edited July 22, 2020 by Daniel
added photo

[gcalberto]

What I usually do is I boil some vegetables (usually kale or zucchini), then put the water and the vegetables in a bucket with tank water. I also throw in some Java moss. After a few days it starts smelling terrible and about week after that you see millions of tiny creatures there. 

After a few weeks it turns into green water, cause I keep it in the sun. I then use this water to feed my daphnia 

[MickS77]

Here's what I came up with. I scrounged up a glass jar, added some lettuce, squeezed some sponge grunge in, filled with tank water, and a shot of easy green. I'll leave it in my patio window sill and see what happens. Thanks for the advice and photos.

Edited July 22, 2020 by MickS77

[Daniel]

How is your infusoria culture working out so far? It must be pretty cloudy by now. Do you have a microscope?

 

 

[MickS77]

59 minutes ago, Daniel said:

How is your infusoria culture working out so far? It must be pretty cloudy by now. Do you have a microscope?

 

 

It is indeed clouded up. I do have a small handheld microscope somewhere. I'll have to find it and see if I can see anything with it. 

[Irene]

I just finished listening the podcast that @Preston John did with Randy. Very interesting, especially the description of how hard it is to keep the spotted congo puffer babies well-fed and how he made tons of infusoria for them. I wonder if Preston would be willing to share his secret recipe for odorless paramecium. Pretty pleeease? 🙂

[Preston John]

Odorless paramecium cultures can be tough to get started, but are amazing once they are set. They are basically a seasoned planted aquarium using plants that grow up out of the water and drop old leaves back into the tank. I’ve found ludwigia sp. to be the easiest for me. Once you’ve got the plants growing, you need to kill off any micro-predators. I just use Safe-Gaurd Dog Dewormer (Fenbendazole) at 0.01 grams per gallon of water. I do this daily until I can’t see any cyclops in the tank. Then You just wait. The bacteria will feed on all the things you killed in the tank, paramecium will have survived and will begin to feed on the bacteria. And the plants keep the water from fouling. then just keep the water topped off and trim the plants as needed. Note if you do trim, dry the cuttings and then add them back to the tank. Do your best to keep cyclops out of the tank or they will eat all the paramecium. They will also eat some fish eggs and very small fry. If they do come back, just treat the tank again. Once the culture has been rocking for a few months, you can also add in some Neocaridina davidi and they will keep the paramecium at a high but stable population so long as you feed them daily. Otherwise you’ll want to harvest the paramecium everyday or so. 

you can also do this without killing off the cyclops, you’ll just go through cycles of heavy paramecium followed by heavy cyclops. Here os a short video of example where the cyclops have just started coming back. 

 

Edited October 28, 2020 by Preston John
I forgot to mention that I also run an air stone for in the tank

[Preston John]

Here are some other ways I’ve cultured them too. I seem to always have at least a few different ways going at any given time. 

 

 

[Preston John]

This is the current version I’m trying out: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4781655/pdf/jove-107-53629.pdf

[Phinny]

A few of the above posts recommend that an infusoria culture be exposed to sun light.  In a green water culture I understand that light is required for algae to carry out photosynthesis. I'm wondering what the purpose of light is in infusoria where algae is not  a major component? 

[Daniel]

I grow little tiny rotifers for my baby gourami. Rotifers are classic infusoria, but the rotifers are also primary consumers. The rotifers need the primary producers, that is the green free floating algae, to live and grow, hence the need for light for photosynthesis to grow the algae to grow the rotifers.

[Phinny]

Thanks for the feedback @Daniel. My understanding was that bacteria were the primary producers in infusoria cultures but perhaps that's not accurate? I thought the purpose of adding vegetable matter to infusoria was to culture bacteria. 

[Daniel]

You are right, the vegetable matter does feed the bacteria.

Vegetable material in water is kinda of like vegetable material in a compost pile. Both provide the nitrogen and carbon to build up large populations of decomposers.

All* primary producers have one thing in common in they make their food using sunlight. Algae and plants do it, but some bacteria do it also, like the famous blue green algae.

But the bacteria in the infusoria culture are heterotrophs feeding on complex organic acids from the decaying vegetable matter, so technically the vegetable matter was the primary producer. And no matter how much heterotophic bacteria you produced in your infusoria culture you still would not have anything near large enough for even the smallest of fry to eat as the bacteria are super small even by baby fish standards.

But microbes like paramecium feast on bacteria and once you get a paramecium population going now you have something the very small fry can eat. I have watched my baby gouramis hunt down paramecium just like wolves.

So bacteria are near the bottom of the infusoria food chain, just not at the very bottom.

But I also think I am beginning to grasp your original point. Which is you could grow infusoria without light. Just feed the bacteria and let the bacteria get eaten by whatever is on the next step up the food chain.

You have persuaded me that it can be done without light.

[Hobbit]

I grow my infusoria cultures with very little light because the one window I’m allowed to use for gross things is pretty small. XD It works!

[Gaara]

@Daniel I love that infusoria tank. You aren’t just raising food, it’s a fun little tank to look at. Why not make another little world to look at?! 

[Smrgle]

If this overcomplicates things and leads to less understanding feel free to completely ignore it, but a parallel can be drawn with vinegar eel cultures. The bacteria feed on the sugars from the apple slices (in this case the apple was the primary producer) and the vinegar eels feed on the bacteria. Fish that eat bacteria tend to go after biofilm, not individual bacterium which are far too small. The ecosystem growing in the paramecium culture takes energy from the sun and repackages it several times until it is in the form of something palatable to the fry. 

As a side note the idea of algae being all classified together is a bit simplified. Bacteria were the first ones on the planet to photosynthesize and photosynthesis has only arisen in bacteria. The organelles that allow things we call algae to photosynthesize are actually reduced bacteria that lost their DNA to the nucleus of the host cell. This is called endosymbiosis.