Does Dwarf Hairgrass need CO2?

Dwarf Hairgrass grows without CO2, but slower and less dense. Liquid carbon or injection makes the difference between a thin patch and a full carpet.

What light does Dwarf Hairgrass need?

Dwarf Hairgrass is a medium-light plant. Most modern aquarium LEDs cover this. Anything sold as planted-tank-ready works. The stock hood on a basic shop tank usually does not.

Is Dwarf Hairgrass safe for shrimp?

Yes. Dwarf Hairgrass 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.

mediummedium lightCO2 helpfulslow growthcarpet

Dwarf Hairgrass

Eleocharis parvula

Also: Hair Grass, Mini Hairgrass

Dwarf Hairgrass forms a dense grass-like carpet in the foreground given adequate light and nutrients. It spreads via runners. CO2 injection significantly speeds establishment; without it, growth is slow and sparse, and algae may outcompete it before it covers the substrate.

Evidence: verifiedConfidence: medium

Substrate mattersCarpet plants establish best in fine nutrient-rich substrate with root tabs — plan this before filling the tank.

Care at a glance

Difficultymedium

Lightmedium

CO2Beneficial

FertiliserNeeded

Growth rateslow

Max height10cm

Placementforeground

Min tank40L

Water parameters

Temperature18–28°C

pH6.5–7.5

Shrimp safeYes

Herbivore risklow

Propagationrunners

Beginner guidance

Plant individual plugs in fine substrate; it will take several weeks to spread. Without CO2, lower expectations on coverage speed. Trim to a few centimetres to encourage lateral growth. Compatible with shrimp, which help clean detritus from the carpet.

Cautions

Slow establishment without CO2; algae can smother it early on.

Sources

Eleocharis parvula. Wikipedia — Species overview: cosmopolitan distribution, aquatic habit, aquarium use as carpet plant.
Eleocharis parvula. Flowgrow — Carpet requirements: high light, CO₂, substrate nutrients.

Fish whose water overlaps

Peaceful freshwater species with overlapping temperature and pH — still run a pair check for the real mix.

Similar plants

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Amazon Frogbiteasy · medium light · no CO2

Plan the tank around this plant

Set a 40L+ footprint, then verify livestock before you buy Dwarf Hairgrass.

Open pair checker Tank builder

Tank hubs: 40L

Related plant guides

Aquarium carpet plants

All plants 40L tank hub

Common questions about Dwarf Hairgrass

Does Dwarf Hairgrass need CO2?: Dwarf Hairgrass grows without CO2, but slower and less dense. Liquid carbon or injection makes the difference between a thin patch and a full carpet.
What light does Dwarf Hairgrass need?: Dwarf Hairgrass is a medium-light plant. Most modern aquarium LEDs cover this. Anything sold as planted-tank-ready works. The stock hood on a basic shop tank usually does not.
Is Dwarf Hairgrass beginner-friendly?: Dwarf Hairgrass is rated medium for difficulty. Plant individual plugs in fine substrate; it will take several weeks to spread. Without CO2, lower expectations on coverage speed. Trim to a few centimetres to encourage lateral growth. Compatible with shrimp, which help clean detritus from
Is Dwarf Hairgrass safe for shrimp?: Yes. Dwarf Hairgrass 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.