Microscopy Thread

[christinna77]

2000x? With a light microscope? With very good objectives you can make 1000x work and have images of reasonable quality, but everything above will be very dark, and you won't be able to resolve more detail than what you were previously seeing with 1000x. The wavelength of visible light limits the amount of detail you can actually resolve.

I know microscopes theoretically can reach 2000x etc. by using a 20x eye piece and 100x objective, but as previously stated you won't get more detail, just a darker image, with less contrast and no additional detail.

It was this one: https://www.amazon.ca/dp/B0BYYY51HJ. 25x eyepiece, a 40x objective and a 2x lens. You're right about the image quality - I almost never use the 40x objective because even without the 2x lens, it's not great. I also have to get way too close to the slide, pretty much touching it to see anything. I think that's actually the only image where I tried to capture it with the 40x objective.

 

[EnterName]

It was this one: https://www.amazon.ca/dp/B0BYYY51HJ. 25x eyepiece, a 40x objective and a 2x lens. You're right about the image quality - I almost never use the 40x objective because even without the 2x lens, it's not great. I also have to get way too close to the slide, pretty much touching it to see anything. I think that's actually the only image where I tried to capture it with the 40x objective.

It's pretty normal to get very close to the cover glass with 40x, 63x, and 100x objectives, but a 40x one should not be touching the cover glass. Maybe you accidentally added two cover glasses at once? They sometimes stick together making it hard to differentiate if you have one or two in your hand. Another possibility would be that they are designed to be used with immersion oil, but this should be noted in the instructions or even better on the objectives themselves. To get the cover glass nice and flat on the slide you can absorb excess liquid by using a piece of paper towel that you hold closely to the edge of the cover glass.

With a better scope (and better objectives) the loss of contrast should change quite noticeably, but it's really difficult to find a scope for around $2000 that's good enough to justify the price while also offering ways to upgrade sooner or later. That's why I can't simply give you something you should buy sorry

 

[EnterName]

Euplotida Ciliate
(Euplotes sp.?)

Note: If you are using the app you might need to switch to a webbrowser to be able to see the video(s).​

I'm currently playing around with the video editing software to improve the quality of my videos. This time I ensured the ciliate stays in the center of the frame which makes observing it easier.

(10x63 PL APO Immersion-Oil Objective Recording)
​

I purposefully shifted the focus around all the time so the little "legs" (ciri) as well as the ciliate's body are in focus from time to time.

​

Common Name	Ciliate
Classification	Order: Euplotida, Genus: Euplotes?
Verdict	Harmless/Beneficial
Size	≤ 160μm
Found	Detritus
Rarity	Common

 

[EnterName]

Aiptasia/Exaiptasia
(Family Aiptasiidae)

Note: If you are using the app you might need to switch to a webbrowser to be able to see the video(s).​

This might be the first time I didn't feel bad for accidentally squashing a sample
The little anemones commonly called "Aiptasia" are pretty much the worst thing that got ever introduced into my tank by accident.

I'm not yet 100% sure, but I think there are multiple species or at least strains that cause trouble in reef tanks. Some are really hard to get rid of as they spread aggressively, while others appear to be quite straight forward to deal with. Unfortunately I got really bad ones, which only my Copperband butterflyfish was able to save me from. He can't reach my filter sump though, so I found a little Aiptasia anemone there.

(End of a tentacle showing cnidocytes and zooxanthellae)
​

The cucumber-shaped things are cnidocytes which corals use to sting whatever causes them trouble. If you take a look at post #1 you can see a clearer image of cnidocytes of another coral. They are filled with a toxin-loaded string called cnidocyst that shoots out and injects toxins in whatever activated them. (There are actually a few activated ones as well in the video). The brown-ish blobs are zooxanthellae (Symbiodinium sp. dinoflagellates) which are the reason why corals can make use of photosynthesis.

Common Name	Aiptasia
Classification	Aiptasia sp. or Exaiptasia sp.
Verdict	Dangerous pest
Size	Usually ≤ 5cm (2")
Found	Coral frags, Rockscape
Rarity	Common hitchhiker

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Aiptasia can reproduce by fragmentation like many anemones, but they are much simpler which allows very small fragments of the pedal disk to fully grow into a fully functional anemone (which would mean tentacles do not grow into new anemones). I hope to find one of their planula larvae as addition to this thread. Apperently some Aiptasia larvae can actively hunt copepod nauplii (see [2]).

(I used the wrong DIC prism but I still like the recording of a ripped of tentacle moving in circles on its own)​

The cnidocytes are very large and appear to be half the tentacles width. Maybe that's the reason why Aiptasia have such an incredible strong sting and can kill other corals so effectively?
The whole tentacle is covered in some sort of cilia which allows it to swim a bit on its own and in this case in a circle.

[1]: https://www.reefaquarium.com/2013/aiptasia-anemones/
[2]: https://www.pnas.org/doi/10.1073/pnas.2311872120