Marimo Moss Ball
Aegagropila linnaei
A charming natural ball of soft green algae that needs almost no care.
| Care Difficulty | Beginner |
| Lighting | Low to Medium |
| CO2 Requirement | Not required |
| Growth Rate | Very Slow |
| Placement | Foreground |
Overview
Marimo Moss Ball (Aegagropila linnaei) is a charming natural ball of soft green algae that needs almost no care. It is a beginner plant to grow, which makes it a great pick for beginners and low-tech tanks.
This guide explains, in plain language, how to grow Marimo Moss Ball well: what it looks like, how much light it wants, whether it needs CO2, how to plant and place it, how to make more of it for free, and the simple mistakes to avoid.
Appearance & Growth
A charming natural ball of soft green algae that needs almost no care.
It is a very slow grower and is normally used in the foreground of the aquarium. Because it grows slowly, it stays tidy and needs little trimming, though slow leaves can gather algae if the light is very strong.
Lighting
Marimo Moss Ball does best under low to medium light. Low to medium light is plenty, so a basic aquarium LED will keep it happy.
Keep the lights on a timer for about 6 to 8 hours a day. Leaving lights on longer usually grows more algae, not more plant, so add light time slowly and watch for any green film.
CO2 & Fertilising
CO2: Not required. This plant grows fine without added CO2, so it suits simple, low-tech tanks.
Feed it with an all-in-one liquid fertiliser (such as API Leaf Zone) added to the water each week. If leaves turn yellow, get holes, or stop growing, that is almost always a lack of nutrients, not a disease.
Planting & Placement
Attach Marimo Moss Ball to wood or rock by tying it with thread or fishing line, or with a little glue. It needs no substrate and will slowly grip the surface as it grows.
How to Propagate (Make More)
Simply cut it and tie or spread small pieces onto wood or rock. Almost any healthy fragment will grow into new moss.
Swapping cuttings is one of the best parts of the hobby - over time a single healthy plant can fill your tank and stock a few more.
Common Problems & How to Fix Them
The most common problem is algae growing on the leaves. This usually means too much light, not enough nutrients, or weak water flow - not a problem with the plant. Lower the light a little, add fertiliser, and improve flow.
Some leaf loss right after planting is normal while the plant gets used to living underwater - keep your light, CO2 and fertiliser steady and new growth will follow. Always remove dead or rotting leaves quickly to keep the plant and water healthy.
Is Marimo Moss Ball Right for Your Tank?
Marimo Moss Ball is an easy, rewarding plant that fits almost any freshwater aquarium, including first tanks and low-tech setups. Pair it with our other plant and aquascaping guides to build a lush, healthy planted tank.