I have a small tank with red cherry shrimps. They love to eat wild mosses I've take from a small stream. They eat it so fast that it cannot regrow by itself in the tank, so I decided to culture it on a separate bottle, among other small wild crustacean: copepods, amphipods, and ostracods; as well as duckweeds, water ferns and snails. I designed some tools to help me handle with these:

cap_mosquito_trap: It prevents the mosquito to enter, or if they do and lay larvae, neither of them can escape. Why not just use the original cap? because this one asure a good simple aeration, and allows me to "feed" the micro-ecosystem easily with rotten food.
tap_cap: I made this to purge or extract water, microalgae and copepods, without disturbing the floating plants. I used a metric thread water dispenser tap.
tap_fix: for this one I used a broken dispenser tap, so I made this very simple fix. I don't the name of this tap, nor if it is available everywhere, so this fix may not work for your tap. I think this one could be the tap I am using
tinynet: A small net that can pass through the bottle neck, and allows me to pick easily ostracods (I have a 2-3mm long specie, pretty big for a ostracod), amphipods, rarely copepods (they are too small), snails, mosquito and dragonfly larvae, and unwanted water bugs. I made it with a "hook" that helps to pick up algae and mosses from the water.

I spend part of my time making these models, letting them available and free for everyone. If you want to support my work, you can contribute with me here:

Found 12 3D-models for “diatom” across many websites

FPV Camera holder for Diatome

Eucampia - Diatom

Diatom sampler - prototype 1

Staurosirella neopinnata

Algae culture 5L bottle set

Diatone Roma F5 Rx Cover Plate

Diatom Cocconeis

Diatom Cyclotella

Diatom Navicula

Diatom Ulnaria

Diatomaceous Earth Applicator

Phytoplankton (Diatoms & Dinoflagellates)