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Marimo moss ball, Aegagropila linnaei

Plant · Algae ball

Marimo moss ball

Aegagropila linnaei · Cool lakes of the Northern Hemisphere (Japan, Iceland, northern Europe) · also Cladophora aegagropila, Lake ball

Photo: Piotr719, CC BY-SA 3.0, via Wikimedia Commons

It is a ball of algae, not a moss, and it likes cool water and low light, so keep it away from heaters and direct sun. Roll it gently every week or two so it stays round and green all over. In 2021 moss balls sold in North America were found carrying invasive zebra mussels, so check new ones and never dump their water outside.

At a glance

Light

Low light

CO₂

No CO₂

Growth

Slow growth

Where it goes

Front

Temperature

15–24°C

pH

6–8.5

Height in a tank

3–10 cm 1.2–4 in

Difficulty

Easy

What it does for your tank

A slow, tidy decoration that shrimp graze on.

Fish that eat or uproot it

Goldfish and some plecos pick it apart, and big fish can break it up.

Growing more

Pull a ball apart into pieces; each one slowly rolls back into a ball.

Grows well with

Same light and temperature, but a different spot in the tank, so they fill it out together.

Amazon frogbit

Amazon frogbit

Plant · FloatingEasy

  • Low light
  • No CO₂
  • Fast growth
  • Floats
  • 20–27°C

Long dangling roots shelter fry, bettas and gouramis, and the plant soaks up nitrate fast.

Central and South America

Amazon frogbit

Limnobium laevigatum

Central and South America

Temperature
20–27°C
pH
5–8
Height
2–6 in · 5–15 cm
Light
Low
CO₂
Not needed
Growth
Fast
Goes
Floating
Difficulty
Easy

More plants. Sends out runners with new plants that break off on their own.

Goldfish and some snails eat the spongy leaves; strong filter flow pushes it under and kills it.

Full care guide

Photo: Cardex, Public domain

Amazon sword

Amazon sword

Plant · RosetteEasy

  • Low light
  • No CO₂
  • Steady growth
  • Middle
  • 20–28°C

A big, classic centrepiece whose broad leaves give shade and are used by angelfish and other egg-layers for spawning.

Central and South America

Amazon sword

Echinodorus grisebachii 'Bleherae'

Central and South America

Temperature
20–28°C
pH
6–8
Height
8–20 in · 20–50 cm
Light
Low
CO₂
Not needed
Growth
Medium
Goes
Middle
Difficulty
Easy

More plants. Baby plants grow on long flower stems; let them root, then cut them free and plant them.

Goldfish, silver dollars and large cichlids tear or uproot it, and some plecos rasp holes in the leaves.

Full care guide

Photo: Salvatore vitale, Public domain

Anubias barteri

Anubias barteri

Plant · RhizomeEasy

  • Low light
  • No CO₂
  • Slow growth
  • On wood, rock
  • 22–26°C

Tough leaves give shade and spawning spots and survive plecos and cichlids.

West Africa (Nigeria, Cameroon, Bioko)

Anubias barteri

Anubias barteri var. barteri

West Africa (Nigeria, Cameroon, Bioko)

Temperature
22–26°C
pH
6–7.5
Height
10–18 in · 25–45 cm
Light
Low
CO₂
Not needed
Growth
Slow
Goes
On wood or rock
Difficulty
Easy

More plants. Cut the rhizome into pieces with a few leaves each.

Herbivorous fish leave its tough leaves alone; big cichlids may uproot it.

Full care guide

Photo: Tocekas, CC BY-SA 3.0

Anubias nana

Anubias nana

Plant · RhizomeEasy

  • Low light
  • No CO₂
  • Slow growth
  • On wood, rock
  • 22–28°C

Tough, low leaves that bottom fish and plecos rest on and that do well in shady corners.

West Africa (Cameroon)

Anubias nana

Anubias barteri var. nana

West Africa (Cameroon)

Temperature
22–28°C
pH
5–8
Height
2–6 in · 5–15 cm
Light
Low
CO₂
Not needed
Growth
Slow
Goes
On wood or rock
Difficulty
Easy

More plants. Cut the rhizome into pieces with a few leaves each.

Almost nothing eats it, so it is a top choice for cichlid, goldfish and pleco tanks.

Full care guide

Photo: Krzysztof Ziarnek, Kenraiz, CC BY-SA 4.0

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