Care Guide
Dwarf Acorus
Acorus Gramineus Pusillus
Care at a Glance
Lighting
Medium
Growth Rate
Extremely slow under water
Growth Form
Mound
Placement
Fore to mid-ground
True Aquatic
No, terrarium plant
Available As
Bare root
About This Plant
Acorus gramineus var. pusillus is a terrarium plant. Dwarf Acorus is sometimes used as an aquarium decoration but will only survive several months completely submerged. After a few months of aquarium use, it must be grown above water for several months to rejuvenate. It is, however a very attractive and recommended terrarium plant where its unusual form and small stature makes it a delightful accent.
About the Acorus Genus
Family — Acoraceae
Acorus (sweet flag) is a grass-like marginal plant. Despite being sold in the aquarium trade, it is not a true aquatic — submerged leaves slowly decline over a few months and the plant must spend most of its time emergent to thrive.
Quick-Reference Details
- Common name
- Dwarf Acorus
- Scientific name
- Acorus Gramineus Pusillus
- Family
- Acoraceae
- Native to
- Eastern Asia
- Difficulty
- Intermediate
- Requirements
- Must have a period of terrestrial growth for good health
- Lighting
- Medium
- Growth rate
- Extremely slow under water
- Growth form
- Mound
- Placement
- Fore to mid-ground
- True aquatic
- No, terrarium plant
- Available as
- Bare root
Difficulty — Intermediate
Grows reliably in moderate-tech tanks. Benefits from steady fertilization and adequate light, but does not require CO2 to survive.
CO2 & Fertilization
CO2 is optional. Growth improves with supplementation, but the plant survives and stays presentable without it.
Tank Size & Setup
Works in tanks 10 gallons and up. Match the plant size to your tank depth for the cleanest aquascape.
Aquascaping & Placement
Place in the midground between foreground carpets and tall background stems. The structure adds visual depth and shelters small fish and shrimp.
Tank-Mate Compatibility
Best suited to paludariums, riparium displays, and pond margins rather than fully submerged community tanks.
Pro Tips for Growing Dwarf Acorus
- 1Not a true aquatic — limit submerged stays to a few months, then move emersed to rejuvenate.
- 2Best used as a pond margin or terrarium plant rather than a submerged aquarium plant.
Common Care Issues
Algae on old leaves
Slow growers accumulate dust and spot algae on older leaves. Wipe affected leaves with your fingers during water changes, and consider adding a few Amano shrimp or Otocinclus as cleaners.
Decline after a few months underwater
This species is not a true aquatic and slowly declines when permanently submerged. Move it to a humid emersed setup (paludarium, terrarium, pond margin) for several months to rejuvenate.
Frequently Asked Questions
How much light does Dwarf Acorus need?
Dwarf Acorus (Acorus Gramineus Pusillus) prefers medium lighting. A standard planted-tank LED fixture run 7-9 hours a day is typical.
Does Dwarf Acorus need CO2?
CO2 is optional. Growth improves with supplementation, but the plant survives and stays presentable without it.
Is Dwarf Acorus good for beginners?
Dwarf Acorus is rated intermediate-level. Grows reliably in moderate-tech tanks. Benefits from steady fertilization and adequate light, but does not require CO2 to survive.
How fast does Dwarf Acorus grow?
Growth rate is extremely slow under water. Be patient — visible new growth may take 3-4 weeks, but the plant is famously low-maintenance once settled.
What fish and invertebrates are compatible with Dwarf Acorus?
Best suited to paludariums, riparium displays, and pond margins rather than fully submerged community tanks.
Can Dwarf Acorus live fully submerged long-term?
No. Dwarf Acorus is not a true aquatic plant and slowly declines after a few months underwater. Use it as a temporary display piece in an aquarium, or grow it permanently in a paludarium, riparium, or pond margin where the leaves can reach air.
Available to Purchase
Dwarf Acorus — $19.99
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