How to Catch Micro-organisms!




You can find micro-organisms everywhere!!! But can you see them? And can you catch them?

Bacteria and viruses are the most common, but typically require special dyes and very powerful microscopes in order to see. And they aren't the most interesting to look at either, you can only see their overall shape (rod, sphere, or spiral shaped) or organization (singular, groups, or chained).

The most interesting kinds of micro-organisms to look at, in my opinion, are bigger eukaryotic or multi-cellular ones. I like them because they can have very unique features and they're see thru, so you can see their internal organs working! And although these guys are a bit more rare, you can easily find them in sources of water like a river or the ocean.

However, if you were to just take any old drop of water, unless it's pretty scummy, you'll only be looking at empty water. This is why we're using a net to catch them!

With this net you can take a quart of water (18,920 drops) or more, and use a filter to get rid of all the water while keeping everything bigger than a micron in there. This lets you see everything all at once, making it a lot easier to find amazing microorganisms! Don't worry it's Super-simple!

Step 1: Gather Your Materials!

You will need:

- A net with very small holes. The smaller the holes the smaller the things you can catch. If your catching larger plankton and stuff, you can actually use women's sheer and will probably be able to look at these guys under a magnifying glass. The middle of the ground size would be nut milk filters But if you want to see very small things like what I show here, you'll want a net in the micron range.

- A 2 liter soda bottle (If you want to filter water more quickly, use a bottle with a wider-mouth).

- Sharp scissors or knife

Step 2: Drill a Hole Into the Cap

Like the title says

Step 3: Assemble!

Place the filter over the top of the end, then screw the cap back on. This should be good enough to seal it, but if you want to, at this step add a bit of silicon adhesive around the inside bottom edge of the cap. So that you can lightly screw the cap back on, which seals it with the silicone adhesive rather than by tightening it, which can potentially cause tears (leading to a microorganism prison escape)!

Step 4: Cut It in Half

Now just cut the soda bottle in half and flip the top part back into the bottom.

The bigger the top half, the more water you can filter at a time, but make sure you can still reach the filter where all your microorganisms are going to be collected.

Step 5: Add Drainage Hole

This is where the run-off water will escape from.

Step 6: Filter and Collect Your Micro-zoo!

Now just pour your pondwater, riverwater, seawater, or whatever liquid into the filter and give it time. It might take a while, but every drop of water that goes through here is one less empty drop of water to look at.

By the way, did you know there are more kinds of microorganisms than there are kinds of animals?! If you kept on looking, you'd honestly never stop finding new things. So what are you waiting for, get out there and explore! And if you find something cool, feel free to shoot it over to: @catalystframe

PS: You will most likely need a microscope to be able to see these guys. If you don't already have one or are looking to upgrade, I recently made a new type of microscope that I think blows everything else out of the water. If you want to check it out, all the information is at: Project page Thanks!



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    11 Discussions


    6 months ago

    Great idea, thanks!


    4 years ago on Introduction

    You should set up a website for this project, and invite people to share photos of different micro-organisms.

    Imagine how cool that would be :D (If you want, drop me a line, I might be able to help with a website, I have a dedicated server thats not doing alot)

    3 replies

    Reply 4 years ago on Introduction

    Wow Thank you so much! Yeah I was actually looking into seeing how I can create a community where people can share what they find. Because my backers for this new microscope range from doctors, veterinarians, scientist, and teachers to people who are just curious. I'm sure they'll see a ton of Really cool stuff and I would love it put it all in one place for people to check out.

    It actually seems like the Easiest way is to use a twitter feed, and I'll just retweet what people send. The microscope works with smartphones/tablets and it would use their existing twitter accounts, so it's really easy for people to share =)

    But I will keep you in mind dan3008, I would like if people can explain what they were seeing with more than 140 characters ;) That's a Great suggestion and I'm really grateful that your willing to lend a helping hand =')


    Reply 4 years ago on Introduction

    Fair enough :)
    I only offered because as a nutritionist I have quite an interest in how micro-organisms grow under different conditions (different foods available), so this is perfect for me, since I can not only sample the water, but see the micro-organisms in it. That and I think its a really worthwhile project.

    offers open, I'm not going anywhere any time soon.


    Reply 4 years ago on Introduction

    Thank you =) and it's awesome to see this project helping you discover more about the world we live in!

    If you find something cool make sure to shoot it over ;)


    Reply 4 years ago on Introduction

    I thought about that too. Probably okay for bigger things, I don't see why not except that it might tear more easily especially once it gets wet and you twist the cap back on. It wouldn't be too expensive to try and find out though =)


    4 years ago

    This is an awesome method to do field research! I have done something quite similar, but I allowed the final solution to fester for a few days. And experimented with like sugars and such. It is amazing what thrives in different conditions! want to observe something really awesome? Do the same thing but add some ethanol to your slide next time you look under the scope. Some of the bacterium and algea will undergo plasmolysis! so cool! nice work!

    1 reply

    Reply 4 years ago on Introduction

    Thanks! Yeah, as someone from a science background I really do hope it helps. Maybe an established field scientist might have better tools, but I'm sure a budding scientist would love to have something like this =)

    Hahaha, great minds do think a like. Yeah, I let some water I collected sit around for a while too, just to see what survives, and maybe catch something new that evolved from it. (Unlikely given the time, but hey I was ready to be surprised).

    Although I should try adding some sugars and stuff.... man who needs the Sims anymore :D

    Thanks so much for all the suggestions, I'll definitely give it a try!


    Reply 4 years ago on Introduction

    Thanks! I was surprised no one put up a instructable for this before, it's a pretty simple job. Glad you enjoyed it =)