2 Giant Japanese Marimo Moss Balls 5cm Live Aquarium Plant Shrimp Java

2pcs around 5 cm

Marimo Moss Balls, also known as Lake Balls or Japanese Moss Balls, are a rare and natural form of algae that grow into soft, velvety green spheres.

Marimo is a unique, living green algae ball suitable for both coldwater and tropical aquariums.

In Japan, it is often given as a gift, symbolising everlasting love and good luck.

Marimo can be kept in a simple glass container as a decorative plant, or added directly to an aquarium or outdoor pond.

If placing it in a container, just use clean tap water and keep it in indirect light. Water changes are only needed every two weeks. No CO₂ or fertilisers required.

Shrimp love Marimo! They often graze on its surface, picking off tiny food particles – making it both a decoration and a natural source of enrichment.

Why choose Marimo

Grows extremely slowly – just 5mm per year, so a 7cm ball is around 7 years old

Will not cause algae problems

Requires very little care

Safe for shrimp, bettas, snails and all aquarium life

Free from snails, pests or parasites

Natural algae control

Marimo absorb excess nutrients from the water, outcompeting nuisance algae and helping to keep your tank or pond water clearer – naturally and without chemicals.

A beautiful, meaningful and easy-to-care-for addition to your aquarium or room décor.

Each Marimo is a living plant that grows with you – a natural treasure.

Care instructions & cleaning

Marimo may contain small grains of sand – a natural residue from where they grow in the wild. This is completely normal

To clean: place in a separate container with clean water and gently squeeze it a few times in your hand

Cleaning is only needed every 10–12 weeks, as Marimo also act as natural filters

If you forget to clean it, no problem – you’ll easily tell when it needs a refresh

Colour variation

Marimo can have slight colour variations depending on the depth at which they grew in nature

In your aquarium, they will adjust – after about three weeks, all balls will look very similar in colour.