Glossostigma

Glossostigma elatinoides

Also sold as Glosso

Synonyms Mud mat

Glossostigma (Glossostigma elatinoides) is a carpeting plant for the foreground, growing to about 3 cm (1.2 in) at a moderate pace. It wants 64–79°F (18–26°C), medium light and CO₂ if you have it, and counts as an advanced plant to keep alive.

At a glance

Type	Carpeting plant
Light	MediumThe least light it survives in, not the light it looks best in.
CO₂	RecommendedWhether it survives without added CO₂ — not whether CO₂ would help it grow faster.
Difficulty	Advanced
Temperature	64–79°F (18–26°C)
Max height	3 cm (1.2 in)Grown submersed, left to mature, never trimmed.
Growth rate	Moderate
Placement	planted in the foreground
pH	5.5–7.5

Before it goes in

Glossostigma needs medium light. Under a low-light LED it thins out instead of filling in.
CO₂ is not required, but without it expect slow growth and a thinner result.
It feeds through its roots, so in plain sand or gravel it needs root tabs; in an aquasoil it does not.
In too little light it stretches upward instead of running sideways, and the carpet never closes.
It stays around 3 cm (1.2 in), low enough to keep the front glass clear.
Its leaves are soft: Goldfish, Common Pleco and Molly will eat it.
It needs about 4 weeks to root. Fish that dig — Goldfish and Common Pleco — will lift it before then.
It counts as an advanced plant: it is not a first-tank pick.

Can it grow without CO₂?

Yes, but slowly. Glossostigma is listed as CO₂-recommended, not CO₂-required: without injection it survives and grows, it just takes far longer to fill in.

How much light does it need?

Medium light — and that is the survival line, not the “it looks better” line. Below it, this one stretches instead of spreading.

How big does it get?

About 3 cm (1.2 in) tall when it is mature and untrimmed, growing at a moderate pace, after roughly 4 weeks to root in.

Will my fish eat it?

Its leaves are soft, so some will: Goldfish, Common Pleco and Molly.

What it goes with

Plants that run on the same light and CO₂, so they can share a tank without one of them being the odd one out: Hygrophila corymbosa 'Siamensis', Water Sprite, Anubias nana 'Petite' and Cryptocoryne wendtii.
Animals that share its temperature range and will not eat or uproot it: Betta, Cherry Shrimp, Angelfish and Bristlenose Pleco.

Often compared with

	Glossostigma	HC Cuba	Monte Carlo
Light	Medium	Medium	Medium
CO₂	Recommended	Required	Recommended
Max height	3 cm	3 cm	4 cm
Difficulty	Advanced	Advanced	Medium

More plants

Plan a tank with Glossostigma →

Sources (5) · checked Sep 2026