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Home > General > Green Foxtail Aquarium Plant: Complete Care Guide for Planting & Growing

Green Foxtail Aquarium Plant: Complete Care Guide for Planting & Growing

green foxtail

Green foxtail is a hardy aquatic plant that looks beautiful in planted aquariums. The plant is suited for freshwater conditions and grows along the foreground. It adds a naturalistic touch to the inside of an aquarium which creates a tranquil environment with the aquarium’s inhabitants. It is a great plant for beginners and has plenty of advantages for water quality. It is easy to grow and maintain in aquariums. The beauty and survival rate of the green foxtail plant has drawn in many aquascapers and novice aquarium keepers alike.

This is a complete care guide to inform you on growing and planting green foxtail that will help you keep the plant growing lush and green.

Green foxtail is also known as:
  • Green bristlegrass
  • Foxtail millet
  • Bottle grass
  • Pigeon grass
  • Myrio green or foxtail
  • Cut leaf Watermilfoil


Quick Summary of Green Foxtail

Care level:  Beginner
Family name:  Haloragaceae
Common name:  green foxtail
Origin:  Bolivia, Rio Guapore
Color:  Green
Growth rate:  Moderate
Minimum tank size:  10-gallon
Water conditions:  Freshwater; 60°F to 86°F
Supplements:  Fertilizer
Placement:  Foreground
Compatibility:  A variety of other low growing plants
Lighting:  Low

The Appearance of Green Foxtail

close up green foxtail
Image By: Jerry Lin, Shutterstock

Green foxtail is a light green color that starts as a dark shade in the beginning but quickly turns a vibrant light green once it has been established inside of an aquarium. The leaves are fine and have a feathery texture. The plant is delicate and can easily be torn by boisterous fish or snails. It is best placed on the ground where will grow dense leaves that form a lush green wall. It grows at a moderate rate at about 1 to 2 inches every week depending on the number of nutrients present in the water. It can grow up to 10 feet tall in large aquariums and maintaining the size of the green foxtail plant is easy and the plant can be cut by the stems. Green foxtail can also grow with the top part out of the water and will produce a flower.

Buyers Guide: Where to Find It?

The green foxtail plant is not readily available in pet stores and should be purchased online. Although it is not easy to find in stores, there are healthy specimens sold online in various sizes. The plant should be shipped relatively quickly at a temperature between 60°F to 86°F so that it can arrive in good shape. The plant should be quarantined for 2 weeks before being placed inside the aquarium. This is to kill off any pathogens or snails that may have hitched a ride on the plant.


General Care & Maintenance

Green foxtail is easy to care for and it does not require harsh lighting, CO2 injections, or strong plant fertilizers. Although there are various care aspects the plant can benefit from. Green foxtail can be planted with the roots fully covered. Leaving the roots exposed puts the plants at risk of being unstable within the water which leads to another placement option, floating in the aquarium. Floating green foxtail provides a great hiding place for small fish or fry and creates a shelter for other inhabitants.

Typical plant fertilizers from your local aquatic shop will cover all the nutrients the plants need for growth. Green foxtail should be fertilized at least once a month if you want it to grow lush and tall.

A healthy green foxtail plant will have no discoloration or decaying leaves. This type of plant is unable to grow in saltwater environments and should strictly be kept in a freshwater cold or tropical environment.

green foxtail plant
Image By: Jerry Lin, Shutterstock

The Habitat, Tank Conditions & Setup

Tank/aquarium size

a minimum aquarium size of at least 10-gallons is ideal. Although this plant will do best in larger aquariums or ponds where it can grow to its full size. Regularly trimming green foxtail will ensure that it remains the size you want it to grow to. Green foxtail is unable to grow in vases or bowls.


Green foxtail acts as an effective nitrate absorber, but it still needs some external filtration to keep it from growing in toxins that will burn the plant. A standard filter with an aeration system is enough to satiate the plant for substantial growth.

Water pH & Temperature

Green foxtail is not too picky when it comes to the water temperature, but prefers a stable temperature between 18°C and 28°C. The pH of the water should be between 5.0 to 7.0. It prefers to grow in low pH and slightly tropical temperatures.

checking PH level of aquarium water
Image By: Joan Carles Juarez, Shutterstock


Green foxtail grows faster when it is placed in a substrate than when it floats in the water. The substrate enables the plant to effectively absorb various nutrients and prevents it from being moved around by the current. Aquatic plant substrate medium provides green foxtail with ideal amounts of minerals required by the plant for color preservation and growth.

Plant Tankmates

Other varieties of low-growing plants can be kept with green foxtail. Keep in mind that the larger green foxtail grows, the more likely it is to compete with nutrients and light with other species of plants.


Green foxtail is not demanding when it comes to lighting requirements, and you can easily keep them with no grow light. They require at least 8 hours of natural or artificial lights. A bright window on the tank can cover their lighting needs.


Tips When Planting

If you prefer to plant green foxtail into a substrate, you should use quality aquatic safe soil rather than sand. If the soil already contains natural fertilizers, then you do not need to add in any excess nutrients. You can also grow green foxtail in glass cups that suction to the sides of the glass, or you can use sinking terra-Cota pots at the bottom of the aquarium. Place the soil inside of the cup and then bury the roots. This is also beneficial if you do not want to add a soil substrate throughout the whole aquarium. Containers with green foxtail planted in also prevent certain fish species from digging them up and creating a mess. Root tabs should be added to the hole you are planting your foxtail in.

aquarium plants
Image By: Public Domain Pictures

The 6 Advantages of Green Foxtail

  • Green foxtail effectively absorbs nitrates which is the product of the nitrogen cycle. The plant has also been known to absorb low levels of ammonia and nitrite which is toxic to fish above 0 parts per million. Since green foxtail grows so fast, it can effectively remove 10pp nitrates within several weeks. Although this does not stop the fact that the water should be regularly replenished to remove toxins.
  • It effectively inhibits algae from growing because it uses most of the nutrients present in the water. If algae do not receive the necessary nutrients, they will not grow.
  • Green foxtail does not shed or lose its leaves inside of the water. So, you should not expect to find parts of the plants floating unattached to the main plant unless a fish or invertebrate has torn it off, or it may just be dying.
  • The plant provides a hiding spot for fish eggs and fry. Many species of fish will attempt to eat their young and their freshly laid eggs, but this is minimized when the fry begins to hide in the leaves.
  • Green foxtail oxygenates the water throughout the daytime when light is present. This does not mean it should replace an aeration system, but it does provide low levels of oxygen to give the inhabitants a boost of fresh ‘air’.
  • It is hardy and resilient enough to withstand many minor mistakes by the carer. Which is yet another reason it is a great beginner-friendly plant.

The 2 Concerns About Green Foxtail

  • At night, aquatic plants use the oxygen present in the water. If the oxygen is not replaced using an aeration system like an air stone, it can suffocate the inhabitants overnight. This means you should ensure there is a good aeration system always running.
  • Green foxtail usually arrives full of snail eggs which can rapidly become a pest invasion for many aquariums. Always isolate the plant before placing it in the main aquarium. You may want to look for aquatic plant-safe products that kill snail eggs or baby snails.

leaves divider leaf


Green foxtail can make a great addition to your aquarium and bring life to any standard setup. The plant is easy to maintain and asks for truly little in return for its growth. Aside from the ease of care, its advantages outweigh the bad. Green foxtail is a uniquely beautiful aquatic plant that can create naturalistic tones when combined with other plants and aquascapes.

We hope this article has helped you find the right way to appropriately care for green foxtail and have your aquatic plant growing well.

Related read: How to Grow Pygmy Chain Sword: Care Guide (Planting & Growing)

Featured Image Credit: Jerry Lin, Shutterstock

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