Dwarf Hairgrass Care: Growing, Carpeting, & Planting

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dwarf hairgrass care carpeting

Dwarf hairgrass is one of the easiest carpeting plants to grow. Well, Eleocharis acicularis and Eleocharis parvula are – and both are sold under the “hairgrass” or “dwarf hairgrass” moniker. This does not make them “easy” aquarium plants. But if you want to put in the time, effort, and – occasionally – money, the results are phenomenal.

Because who doesn’t love a lush lawn?

But if that doesn’t sound like something you want to do, I suggest you find a different plant. Anubias, java fern, and guppy grass are all basically bulletproof. I would note that dwarf hairgrass is, all around, not a cheap plant. Mostly because it’s not the easiest plant.

If you’re feeling up for a do-able challenge, read on and I’ll tell you everything you need to know about growing a lawn in your fish tank!

Disclosure: we’re reader-supported! So if you buy a product I recommend, I might make some coffee money at no cost to you.

Table of contents

dwarf hairgrass species card


Dwarf Hairgrass Natural Habitat

It’s weird for me to think of “wild” dwarf hairgrass when all we see are pictures of these neatly trimmed lawns inside fish tanks. But, of course, it does live in the wild.

The natural range of dwarf hairgrass – or hairgrass – depends on the species in question. Between the three, they range from North America to Europe to Asia and South America. All species are found in shallow areas with high lighting, such as around shorelines. For the most part, the care of all three species is about the same.

Dwarf Hairgrass Care

Difficulty: Moderate – can be frustrating
Size: 3 – 5″ (7 – 12cm)
Propagation: Runners
Fertilizer: Root
Speed of growth: Depends on conditions
Temperature: 50 – 83F (10 – 20C)

pH: 6.5 – 7.5 – though likely higher
Hardness: 2 – 10 dKH
Placement: Planted
Origin: Species-dependent
Aquascaping: Foreground to midground
Availability: Very common

Planting your dwarf hairgrass is a critical – but often overlooked – step. If done incorrectly, your plant won’t carpet well or it’ll die completely. 

When planting, bury the roots entirely in the substrate, but be aware that all blades of the “grass” need to be above the substrate. Most people will attempt to plant the entire pot in one bunch and hope that the plant will carpet. Although more time-consuming, a better plan is taking the plant out of the container.

Like This
Not like this

Once out, separate it into smaller chunks with a handful of blades per piece. Plant those chunks deep into the substrate with some tweezers far enough apart from each other to allow for growth. If you trim the some of the blades a few days after planting, it will stimulate it to grow horizontally. 


Dwarf hairgrass needs a moderate to high level of lighting in order to grow. It also can’t have any plants around that will block the light since it can’t photosynthesize in shaded areas. The lower the lighting, the taller the plant will grow, the higher the light, the more horizontally it will grow. This makes a huge difference between a carpet and long, scraggly hairs.

However, if you want your dwarf hairgrass to carpet, you’re going to need some bright lights. Like real bright.

Dwarf hairgrass

I suggest something above 45 PAR, but over 60 would give you better odds. If you don’t know what a PAR is, it’s nothing to seriously worry about. It’s the measurement of light that’s available to the plants to use. If you can, I would suggest a customizable light so you can fine-tune if you find you’re getting algae issues.

If you don’t know where to start, I’ve included some tried and true lights below – including par specs.

Fertilizers & Substrates

Dwarf hairgrass grows best with liquid fertilizer and nutrient-rich substrate – it’s near impossible to grow it without one of the two. Sand is another popular option for dwarf hair grass substrate as it’s easiest to push the roots through. The plant has an easier time sending runners over sand for the same reason; you can opt to add a layer of aquatic plant soil beneath the sand which accomplishes both tasks nicely. 

dwarf hairgrass

Additionally, it does much better with Co2, but most plants do. If this sounds like an insane amount of research, I have some of the best Co2 kits, soils, and fertilizers below. If you want to do your own legwork, be aware that this plant needs root tabs, not liquid fertilizer.

Common Problems

I hope we’ve already established at this point that dwarf hairgrass is not without its hair – er, make that fair – share of issues. But, the above aside, here are the most common issues dwarf hairgrass has in tanks:


plant melting

Melting is incredibly common in aquatic plants as most of them are grown above water. If you pluck off the dying parts of the plant before they start rotting, the new aquatic growth should appear soon enough, and it’ll do just fine.

carpeting plant not carpeting

It’s Not Carpeting

When a carpeting plant isn’t carpeting, it usually comes down to a lack of…

  • Lighting
  • Nutrients
  • Proper substrate

It could’ve also been planted incorrectly. If all of those are in check, try giving it a trim to see if that helps.


algae on plants

Algae growth is a common problem, it will eventually choke out plants or outcompete them. Algae is a sign of an unbalanced ecosystem, either there is too much light or there are too many nutrients in the water, without one of these opportunities it wouldn’t be able to take hold.

Dwarf Hairgrass Maintenance

Dwarf hair grass will need regular trimming to ensure that the bottom of the plant isn’t deprived of water movement. Trimming dwarf hair grass also stimulates the plant to grow horizontally rather than upwards.

Trimming might be a skill that you need to invest in to ensure that at looks natural and stead of choppy. Cutting dwarf hairgrass is as simple as removing the tops of the leaves by using angled scissors – a lot like pruning a lawn with scissors.   

It’s a good idea to keep a net handy to get as much a the trimmings out of the water column as possible. Its possible excess trimmings left in the tank could clog your filter or, at the very least, rot. If you have snails or other cleanup crew members in the tank, rotting likely won’t be an issue. But, if you’re using a canister filter or a hang on back, clogging could potentially become a problem. 

Additionally, you’ll likely need to consistently reevaluate your lighting, fertilizer, and Co2 schedule. Once it starts carpeting quickly, you may need to play around with these numbers once a week to keep growth on track. Also, if you opted for nutrient soil you’ll need to replace that every few years or add root tabs after that if you don’t want to rip your tank up.


Propagating dwarf hairgrass isn’t as easy as it is with some other plants, you have to wait for the plant to decide to propagate on its own. Any cuttings of the plant won’t be able to grow their own roots, so it’s best to wait for dwarf hair grass to send off runners. Once you see them, wait for those shoots to develop blades of grass.

From there, you can cut off sections of the runners from the mother plant if you want to. However, if you’re trying to go for a carpet, this probably isn’t the best tactic.

You can see some runners under the soil

If propagation isn’t happening as fast as you like, you can speed up the process with higher lights, fertilizers, Co2, trimming the top to encourage shoots, or raising the water temperature if it’s in the low range. But, again, you’re just trying to help the plant propagate – you can’t force it.

What About Fish?

Dwarf hairgrass, although awesome to look at, is not the best choice for most tanks. Particularly if you already have fish in the tank.

Most shrimp and tetras would be fine. Most catfish, cichlids, loaches, and, well, everything else, will either hate that they can’t dig or dig them up so they can dig. Additionally, most fish are skittish and don’t like bright lights. Oh, and dwarf hairgrass only grows well in shallow tanks – generally smaller is better as well.

So if that sounds out of line with the kind of fish you wanted to (or already) have in your tank, you might want to rethink things. Especially if you want to see happy animals doing their thing. I’ve included a few fish ideas below to get you started, but it’s definitely not a definitive list. Before you dismiss it, I did try to include some cool suggestions for you.

Ember Tetra (Hyphessobrycon amandae)

Ember Tetra

Ember tetras are bright, fun, tiny, shoaling fish that occur in South American black waters. They’re hardy, peaceful fish that are often described as active, bold, and playful. They also enjoy a planted tank, but be mindful that they do like to swim in open space, so be sure to include that in your layout. They enjoy their numbers a little higher than most shoaling species, 8 is recommended.

pH: 5.5 – 7
dKH: 1 – 10
Temp: 68 – 82 F (20 – 27 C)

Size: 3/4″ (2 cm)
Temperament: Peaceful and active
Swimming: Top to midwater shoaling

Pencilfish (Nannostomus sp.)

beckfords pencilfish

Pencilfish is a genus containing 19 currently recognized species. Some popular options are diptails, Beckford’s, and coral. Although it’s a large genus, the care is similar for all of them and you should aim for a shoal of at least six. 

Research into a specific species and their requirements is strongly recommended. 

pH: 5.0 – 7.0
dKH: 4 – 12
Temp: 74 – 82F (23 – 27C)

Size: 2″ (5 cm) species dependent
Temperament: Peaceful
Swimming: Mid to top

Harlequin Rasbora (Trigonostigma heteromorpha)

harlequin rasbora

Harlequins are a shoaling species that prefer friend groups of six or more. They’re not known to be nippy fish and are quite peaceful as long as they’re provided plants, space to swim, and the company of their own kind.

pH: 5 – 7.5
dKH: 1 – 12
Temp: 70 to 83 F (21 to 28 C)

Size: 2″ (5 cm)
Temperament: Peaceful
Swimming: Mid to top-water shoaling

Lambchop Rasbora (Trigonostigma espei)

You can think of the lambchop as a smaller cousin to the harlequin rasbora (Trigonostigma heteromorpha) they look and act similarly and their care requirements are about the same. These guys are just a bit smaller with slightly different coloring.

pH: 5.5 – 7.5
dKH: 1 – 10
Temp: 74 – 83F (24 – 28C)

Size: 1.2″ (1 cm)
Temperament: Peaceful shoaling fish
Swimming: Mid to top

Cherry Shrimp (Neocaridina davidi)

neocaridina shrimp

Neos enjoy munching on decomposing plant matter, grazing on algae, and picking sunken pieces of wood and plants clean. This makes them a perfect addition to a naturalistic tank. They come in a variety of colors including the oh-so-common cherry shrimp!

pH: 6.5 – 8.0
dKH: 8 – 20
Temp: 70 – 79 F (21 – 26 C)

Size: 1.6″ (4 cm)
Temperament: Peaceful
Swimming: Anywhere there’s food to pick, but usually bottom

Toucan Tetras (Tucanoichthys tucano)

These guys are hard to find (but I know a few good spots if you want them!) And they’re completely worth hunting down these rare gems. They’re a peaceful shoaling fish that need to be kept in groups of six or more and the only known wild population exists within a 200-meter range in Brazil.

pH: 4.0 – 6.5
dKH: 1 – 8
Temp: 68 – 83F (20 – 28C)

Size: 1″ (2 cm)
Temperament: Peaceful shoaling fish
Swimming: Mid to top

Neon Tetra (Paracheirodon innesi)

neon tetra

Neon tetras are shoaling fish from the Amazons that are best kept in groups of six or more to be happy. They’re not usually nippy and are active and outgoing if housed properly. They prefer blackwater setups but will do fine in a range of parameters. It’s worth noting that commonly available stock isn’t as healthy or hardy as it used to be even ten years ago.

pH: 4.0 – 7.5
dKH: 1 – 12
Temp: 70 – 83F (21 – 28C)

Size: 1.5″ (4 cm)
Temperament: Peaceful shoaling fish
Swimming: Mid to top

Black Neon Tetra (Hyphessobrycon herbertaxelrodi)

black neon tetra

Not to be confused with the black tetra (or “black skirt” tetras) or neon tetras (Paracheirodon innesi,) the black neon tetra is a separate species. They do best in groups of eight or more – but more is always better when it comes to shoaling fish. They have the peaceful demeanor of the neon tetra without all the health issues. 

pH: 5.5 – 7.5
dKH: 4 – 9
Temp: 73 – 81F (23 – 27C)

Size: 1.5″ (3 cm)
Temperament: Peaceful shoaling fish
Swimming: Mid to top

Silvertip Tetra (Hasemania nana)

If you like fish that will follow your finger like ravenous sharks, these are your fish. They’re a nearly unspookable little shoaling fish that like to be kept in groups of six or more. 

pH: 6.0 – 8.0
dKH: 5 – 20
Temp:  74 – 82F (23 – 28C)

Size: 2″ (5 cm)
Temperament: Active shoaling fish
Swimming: Mid to top

Pea Puffer (Carinotetraodon travancoricus)

If you’re up for a little bit of a challenge, these guys are super rewarding once you put in some work. They’re tiny, smart, curious, personable, and full of sass – plus no salt.  

pH: 6.8 – 8.0
dKH: 5 – 25
Temp: 72 – 82°F (22 – 28°C)

Size: 1″ (2.5 cm)
Temperament: Varied
Swimming: Everywhere

If you want to do some additional research, I would suggest that in addition to being small and top-dwelling, you consider their natural habitat. Most small fish can be found around floating vegetation or in densely planted areas. If the fish you want isn’t described as outgoing or personable and comes from those sort of locations, it’s probably not the best choice with this setup.

Further Reading & Resources

Green Machine – Working With Carpeting Plants & Grasses

Aquascape Addiction – Best Substrates For Planted Tanks

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