Does Duckweed need CO2?

No. Duckweed grows in low-tech tanks without CO2 injection or liquid carbon supplementation.

What light does Duckweed need?

Duckweed is a low-light plant. Standard aquarium LEDs cover this with room to spare. It is one of the plants you can light from a basic shop hood and still get growth.

Is Duckweed safe for shrimp?

Yes. Duckweed is safe in shrimp tanks. The usual quarantine still applies: any plant from a commercial nursery should be soaked and rinsed first to flush copper and pesticide residue.

Image: Wikimedia Commons — attribution available on this site.

Plant appearance can vary with lighting, nutrients, CO₂, and whether it is grown submerged or emersed.

easylow lightNo CO2 neededfast growthfloating

Duckweed

Q: Is Duckweed beginner-friendly?

Duckweed is rated easy for difficulty. Good for tanks with goldfish or other herbivores that will eat it as food. Nearly impossible to fully eradicate, only introduce if you accept a permanent presence. Skimmer/overflow tanks spread it fast.

Lemna minor

Duckweed is the smallest flowering plant and one of the easiest floating plants to maintain. It is very fast-growing, highly effective at nutrient export, and shades the tank well. A double-edged plant: extremely useful for nutrient control, but notoriously hard to remove once introduced.

Care at a glance

Difficultyeasy

Lightlow

CO2Not needed

FertiliserNot essential

Growth ratefast

Max height1cm

Placementfloating

Min tank5L

Water parameters

Temperature5–30°C

pH5–9

Shrimp safeYes

Herbivore risknone

Propagationdaughter fronds

Beginner guidance

Good for tanks with goldfish or other herbivores that will eat it as food. Nearly impossible to fully eradicate, only introduce if you accept a permanent presence. Skimmer/overflow tanks spread it fast.

Cautions

Very difficult to remove once established.
Can clog filter inlets if sucked in.

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