The Complete Guppy Grass Care Guide For Dummies

Everyone wants an aquarium that looks like a small ocean with a variety of aquatic plants and beautiful fishes floating inside it. But many of them hesitate to do so because they think it requires a lot of care and maintenance to grow a plant in an aquarium and also it will need many additional pieces of equipment for it.

But is it true?

No, not at all. If you want to grow low maintenance aquatic plants in your aquarium, then Guppy Grass is one of the perfect choices for you. The common water Nymph aka Guppy or Najas Grass is very easy to grow in the freshwater aquarium and does not require any special equipment.

Guppy grass is one of the fastest-growing aquatic plants. It is a very popular aquarium grass used in guppy fish tanks by almost all aquarists.

Read on if you are keen to know what exactly is Guppy grass and how we should maintain it in the aquarium tank.

What Is Guppy Grass?

Guppy Grass Care Guide

Guppy grass is also known as Najas Guadalupensis. It is generally found in ditches, ponds, and streams.  It has very speedy growth.

You can grow it as a floating or rooted aquatic plant. It is good for fry tanks. It removes unwanted toxins from the water and helps to oxygenate it. It can easily be rooted in the substrate or floated in the water and can grow very quickly.

Guppy grass is one of the most preferred hiding spots of the aquarium fish. They generally swim around this plant. Guppy grass, in general, is the most versatile and low maintenance aquatic plant. 

Guppy Grass Habitat 

Guppy Grass is native to North, South & Central America. It is also available in Canada, the Caribbean, Mexico, and Asia.

There are different habitats of Guppy grass such as salty lakes, still streams, trenches, ponds, and freshwater. It can also be grown in canals, gutters, or local waterways. It is considered to be one of the fastest spreading species in many countries.

Appearance and Growth Habits

Guppy grass has slim and slender stems that are very long. The leaves of the guppy grass are 3 cm long and 1 to2 mm wide. It has many branches. The maximum height of the plant goes up to 90 cm. 

The Guppy grass has thin transparent green-colored leaves. The structure of the edges of the guppy leaves is like tiny unicellular teeth. It has white roots and small flowers that are generally unnoticeable. 

Due to its quick and rapid growth, this Najas grass is one of the most popular choices of aquatic experts. It does not require specific lighting conditions or CO2 injection for speedy growth. You can grow it in both the ways floating as well as rooted in the substrate.  It can easily propagate or grow by stem cutting.  

How to Use Najas Grass in Your Aquarium?

As we already know that Najas or Guppy grass is a perfect option for any planted tank and it is ideal for shrimp tanks and breeding set-ups.

Originally it is one of the favorite grass of the guppy breeder, that’s why it is called ‘guppy grass’. But it’s easy propagation, fast growth, wonderful pattern, and low maintenance make it a favorite to all grass lovers. 

Uses of Najas

There are many uses of Najas grass in a freshwater aquarium. Some of them are:

  • Thick stems and dense leaves of the Najas grass provide shelter to the delicate and soft animals. It also traps the tiny particles of food that are used to feed them.
  • This grass is an excellent food for vegetarian fishes like goldfish, algae-eating fish, etc.
  • The Najas grass removes toxins like nitrate, nitrite, and ammonia and it also absorbs extra nutrients from the water and keeps the tank clean. 
  • This grass is generally used in heavily stocked fish tanks to reduce the load of filters. As it has algae-fighting properties, it prevents the growth of unpleasant algae in the tank
  • It produces a lot of oxygen, so it is very helpful in rejuvenating the dead zones of the fish tank.
  • Najas grass gives a bright light beautiful look to your aquarium tank. You can grow it in any of the ways you like. 

How Do You Preserve Guppy grass?

Guppy grass is one of the easiest aquatic plants to grow in your fish tank. It does not require much effort. Rather, sometimes you find it difficult to control its rapid growth.

Some key points should be kept in mind while growing Najas grass in your aquarium tank

Size of Water Tank

You can keep the guppy grass in a nano tank, but due to its fast growth, the recommended tank size is a minimum of 10 gallons i.e., approximately 40L for proper development of this plant.

Type of Water, Hardness & Temperature

  • Generally, Guppy grass can comfortably grow in both hard and soft water.
    • The recommended hardness level ranges from 2 to 20H.
  • Guppy grass can easily grow in various temperature conditions.
    • The ideal temperature condition for growing the guppy grass is between 20°C-26°C i.e., 68-79°F.  
  • The pH value ranges between 6 to 8 is ideal to grow the guppy grass properly in the fish tank.


Generally, in many of the fish tanks, Guppy grass grows as a floating plant, but you can also root it in a variety of substrates in your fish tank. You can choose any varieties of the grass, but remember to keep sufficient nutrients in the water for proper growth and development of Najas.

Lighting Conditions

There is not much illumination required to grow the Guppy grass. It has excellent growth in the medium to low light set up for 8-12 hours daily. For beautification, you can use more lights to give a greener look to your aquarium. It gives you a reddish tint in high-lights. But high-lights may burn the leaves of the grass pretty fast.

Water flow

Low water flow conditions are ideal for the proper growth of Guppy grass. It helps to make the grass grow better and also does not allow the filter to clog. 

Do You Have To Plant Guppy Grass?

As we discussed earlier in this section that Guppy grass can grow in the tank in many different ways. These methods include:

Plant the Grass

If you want to plant the grass, first you have to cut the stems of grass into several pieces and plant them deep into the substrate by maintaining proper space between them. It does not have a very strong root system.

Allow Floating

If you select floating the grass in the water column then divide the stems and place those stems in the water column. Most of the aquarists generally prefer to leave the grass floating in the water instead of planting it into the substrate.

You can use both methods in your fish tank. Plant some of the stems into the substrate and leave the remaining stems floating in the water column. 

Does Guppy Grass Grow Roots?

As we know Guppy grass can easily draw nutrition from the water column, so you do not require any separate fertilizer tabs or any type of sand, soil, or stones.  They do grow white roots and have tiny flowers near the base of them.

In fact, you can grow the Guppy grass by floating it in a bare-bottomed tank. Whatever you may prefer, the choice is all yours.

As far as maintenance of Guppy grass is concerned it is very easy to maintain. You can even say that it grows without any maintenance if you take care of some of the key points about Guppy grass:

  • Regular change of water is the key to make the Guppy grass grow very speedily. It is also helpful in replacing the essential nutrients and minerals that it absorbs from the tank’s water. 
  • Guppy grass removes the toxins like ammonia, nitrate, and other organic wastes from the tank and makes it clean, and also increases the oxygen level. 
  • If you find a slow growth of Guppy grass or observe any yellowishness in leaves, it is because of carbon deficiency. A balanced liquid fertilizer once a week can help to boost growth. You do not need to use CO2 injection to increase its growth.
  • As Guppy grass has speedy growth it can create obstacles in penetration of light to the plants placed at the bottom.
  • To avoid this, timely trimming is required. Trimming of the lower section of grass is important as it does not look attractive if it lasts in the tank for very long. You can either dispose of the trimmed grass or give it to your hobbyist friends for their fish tank.

Guppy Grass Life Cycle

Guppy grass or Najas grass is an annual aquatic plant that spreads very fast. The stems of the grass are very delicate and break easily.

This broken and fractured stem quickly form white color roots while floating in the water. This grass also produces small white flowers that are unnoticeable and do not produce any seed or fruit in the tank.

Is Guppy Grass Good For Aquarium?

Guppy grass or Najas grass is a commonly used aquatic plant in most aquarium tanks because it can easily grow in all types of water.

Whether it is cichlids or barbs or rainbowfishes in your tank, these grasses provide well-oxygenated or clean water throughout the year to these communities. No doubt it is very beneficial to all types of fishes.

Best Undergravel Aquarium Filters

Fishes like Guppies, Platys, Mollies, Swordtails, etc. use the bunches of guppy grass for sheltering their fry and raising them safely. Guppy grass trap tiny particles of food in their stems and later feed them to different communities such as Tetras, Minnows, Shrimp, Mystery, Assassin snails, Omnivorous catfishes, etc

Do Guppies Eat Guppy Grass?

Guppies do not really eat them but it does provides them with a number of benefits within the aquarium ecosystem.

Also Read:  How To Introduce Guppies To A New Tank?(3 Simple Steps)

Gives Shelter

Guppy grass provides shelter to the fry because it has many hiding spots. The little fry is raised safely by hiding from predators. 

Removes Toxins

Guppy grass removes harmful toxins like ammonia, nitrites, and other heavy metals from water and maintains the water quality within a tank. 

Helps in Breeding

It is one of the most ideal breeding spots for the little ones like shrimp, and other egg scatterers. They can easily lay eggs on these spots and nurture them safely.

Provides Food

For herbivores and omnivores, it is a good source of food. Fishes like Goldfish, Cichlids, Silver dollars, etc. can eat the leaves of Guppy Grass and satisfy hunger. 

Controls Algae Growth

Guppy grass has anti-algae properties that help to reduce the unwanted growth of algae in the fish tank and maintains the speedy growth of grass.

Increases Oxygen flow

It provides a lot of oxygen in the fish tank therefore it is very useful to reenergize the dead zone of the aquariums.

Improves Aesthetics

Guppy or Najas grass also improves the aesthetics of the fish tank. It gives a natural look to your aquarium. Communities in the tank also experience natural surroundings all around. 

Helps to grow Biofilm

Guppy grass or Nazas grass is an alternative place to support the growth of biofilm. It is a perfect diet for new-born shrimplets and fries.

Problems with Guppy Grass

Grows Speedily

One of the most common problems with Guppy grass is its speedy growth. The growth of this grass is so quick that time to time trimming is a must otherwise your tank will overrun and create a mess.

Blocks the Light

Because of its rapid growth, it covers a larger area of the tank and blocks the light penetrating the lower section of the tank. So, proper trimming once a week is required to avoid blockage. 

Breaks Easily

The stems are very delicate and prone to breakage If left unattended the broken side also develops a new part of the plant. This may create a mess in the tank.


Whenever you put the stems of guppy grass in the tank it starts melting because of the changes in the growing environment and water type. It takes some time to adapt to these changes and start to regrow to get its original beauty.


The presence of Guppy or Najas grass in your aquarium tank creates a beautiful surrounding for all organisms. It has a lot of benefits for your fish tank. It is a low maintenance speedy grow grass that removes harmful toxins from the fish tank and provides a well-oxygenated environment to the aqua communities like shrimp, fry, etc. 

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