Microscopy tips (including for viewing bacteria on fermented vegetables)

Looking for microscopy tips!

With my students, I’ve been trying to find tardigrades today and finally did, but am struggling to get good focus or crisp results, so wondered if people had some tips.

We soaked moss for 24 hrs in tap water and using a HDMI USB microscope I was able to scout them out alongside some nematodes in a larger container. I then added some of the solution to a petri dish, put it under a compound microscope and still had visibility… but it was a bit blurry.
( a lot more than most other people’s microscopic obs I see here on iNat).

Focus seems really hard on the higher magnifications!
The highest magnification we have is 100X but I read that’s more for use with oil - can we also use it for water and tardigrades? Are there recommended methods for transferring from petri dish to slide …or in general to up magnification without losing sight of it?

My students actually wanted to view bacteria on fermented vegetables though…
For this, should we be able to see movement of bacteria with 40x or 100x or do we need time lapse?
And how best to prepare a slide for this sort of matter? Do we need to soak in water like the moss?

What other substrates or locations or approaches are also recommended to find microscopic life?
( I would also like to find diatoms… and was curious about what microscopic life can be found in intertidal zones or geothermal areas here )

Any pointers welcome! Thanks everyone :)

P.S. These are the tardigrade pics -

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Hi there! I also recently got a microscope and started microscopy, so here’s what I’ve learned.

What this means is that you have a slide, but then you place a little bit of something called immersion oil on top of the cover slip, and then lower your 100X objective into the immersion oil. I don’t have 100X though, but you can watch this video: https://www.youtube.com/watch?v=wBGmdAqApcY

I look for bodies of water such as ponds, lakes, and oceans. Generally I’ll scoop some water, put a drop of the water on the slide, and put a cover slip on it. I recommend getting some sediment with it, because that’s where microbes live - clear water doesn’t have many microbes in it. I’ve learned that diatoms are easy to find, but hard to identify.


I remember reading once that one of the richest and convenient sources of micro-subjects (including Water Bears) is the sludge in the bottom of an eavestrough.


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