How To Grow Crystalwort (Riccia Fluitans): Planting, Propagation, Care & More

How To Grow Crystalwort (Riccia Fluitans): Planting, Propagation, Care & More

March 26, 2024

How To Grow Crystalwort, also known as Riccia fluitans, is an aquarium moss plant that is popular amongst aquarists. Thanks to its ease of maintenance, it is one of the best mosses for beginner aquarists to grow and care for.

When looked after correctly, crystalwort can become an eye-catching attribute in any type of aquarium. 

If you own an aquarium, you will want yours to stand out from the crowd. We all want unique aquariums, and that is why many of us fill them with different species of fish.

But, although this is a sure way of creating a distinct aquarium environment, there are other ways to achieve unique aquariums.

For many, having beautiful plants in their tanks is what sets theirs apart from anyone else’s. One plant, in particular, can make any tank come to life. This is, of course, Riccia Flutians (crystalwort).

Crystalwort is a very versatile plant that is also pleasingly simple to care for. With its moss-like characteristics, this plant is a popular and excellent alternative to the more widely used Java moss.

How To Grow Crystalwort (Riccia Fluitans): Planting, Propagation, Care & More

It sports a bright green hue that is perfect for decorating the backdrop and foreground of tanks filled with anything from shrimps to plants. 

This fast-growing plant can quickly take over an aquarium, but not so much that you can’t reign it in. Even amateur hobbyists will find it relatively simple to grow Riccia fluitans in their tanks.

Whether you’re new to the aquarium game or experienced, you may be looking to add the crystalwort plant to your aquarium.

If so, you need to learn how to grow and care for it effectively.

Today, we are going to show you just that with our extensive guide on how to plant, propagate, and care for your crystalwort plant in a freshwater aquarium.

Let’s get straight into finding out a bit more about this fascinating aquatic moss.

Crystalwort – Origins

Crystalwort, or Riccia fluitans, belongs to the family Ricciaceae.

This is a family of minute liverwort that have a flat thallus (lacks roots and a vascular type system, and is not differentiated into a stem and leaves).

First described in 1753 by Carl Linnaeus, it was first used by Taksahi Amano, a Japanese aquascaper. Amano was the first to use this bright green, floating plant in a nature aquarium and managed to grow it underwater.

Although different countries have their own version of crystalwort, such as Thailand, Singapore, and regions in Europe, it is the Japanese kind that can only survive fully beneath water.  

Crystalwort – Common Names

You may have heard of crystalwort being referred to as other names, such as floating crystalwort. This is because the plant is often found floating in nature.

This is why both its scientific and common names refer to its floating characteristics. 

Scientifically named ‘Riccia Flutians,’ the word ‘flutian’ derived from the Latin meaning ‘floating.’

As for its ‘crystal’ name, this is because of its leaves that form a crystalline structure at their ends. 

Crystalwort – Habitat 

Crystalwort is described by many as being ‘cosmopolitan’ due to being found in many regions of the world such as the Americas, Eurasia, and Africa. 

As an amphibious liverwort, crystalwort had adapted to live on moist ground, such as soil. But, it has also evolved to thrive in water.

Here, it floats on the surface of water or, if it’s the Japanese type, stays submerged below the water, attached to other plants, or to the bottom of a tank. 

If wild crystalwort is fully submersed, it tends to prefer quieter and shallower waters such as swamps, ponds, ditches, and calm streams. 

Crystalwort – Appearance And Size

Crystalwort shares similar characteristics with other Riccia plants.

One similarity is that it has thick groups of vividly green threads. It also grows in a spherical-shaped cluster but is a little flat, too. 

Crystalwort is a perennial plant that branches out widely. When growing, various shoots spread around with fork, almost Y shapes.

The size of crystalwort plants is generally the same across the board.

The typical thallus length of this Riccia plant is approximately 0.5 to 2 cm or ⅕ to ¾ inches, while its width is usually about 1 mm (1/25 inches).

The plant’s body maintains buoyancy in water thanks to air pores. Also present are certain cells that contain starch and chlorophyll.

These are responsible for producing energy to help crystalwort thrive. 

If crystalwort is grown submersed in water, root-like structures are formed. These are known as rhizoids and they help to keep the thallus anchored to the substrate.

An interesting difference between the aquatic type of crystalwort and the terrestrial form is that the latter is twice as wide as the aquatic kind.

Therefore, terrestrial Riccia fluitans tend to grow spore capsules, whereas the aquatic form typically reproduces asexually.

Crystalwort – Care Guide

Crystalwort - Care Guide

Now we understand a little more about what crystalwort plants are and where they come from, let’s learn how to care for these plants properly.

Crystalwort is a pleasingly easy plant to grow. It does not need a great deal of care or preparation to grow healthily in a freshwater tank.

Of course, that doesn’t mean they require no care whatsoever. Like any household plant, you will need to keep on top of things to ensure your crystalwort doesn’t die.

When Riccia fluitan is cared for correctly, it can help make your tank more healthy than ever. It does this by producing more oxygen!

As well as helping give life to your tank, you can sculpt the plant into any design to fit and suit your tank.

Nevertheless, crystalwort grows best in tanks that have a low water flow, as this is the kind of habitat it is naturally found in.

If the current is too strong or quick, the stems could easily snap, leaving a piece of the plant floating around your tank.

Let’s take a look at what sort of tank environment is best for your crystalwort to thrive.

Tank Lighting

The lighting required for Riccia Fluitans to grow and remain healthy is determined by where you grow the plant within your aquarium.

If the plant is grown at the base of the tank, it will need more light compared to being grown on the surface. 

For crystalwort grown on the surface of an aquarium, low-level light should suffice. For healthy growth, however, we suggest using high-level light, such as an LED light.

Tank Temperature 

The temperature that your crystalwort plant dwells in is very important. However, Riccia fluitans is capable of surviving in a vast range of temperatures, ranging from 59 to 85 degrees Fahrenheit (15 to 30 degrees Celsius).

Nonetheless, it tends to thrive best in temperatures between 68 and 79 degrees Fahrenheit (20 to 26 degrees Celsius).

PH Levels

In general, Riccia fluitans require a pH level between 6.0 and 8.0. Within this range, crystalwort can grow and thrive in aquatic environments with many species of fish.

CO2 Requirement

It is generally suggested to give submersed crystalwort pressurized Co2 injections. These will help the plant grow a more vibrant color and stronger structure.

All in all, these injections will boost the plant’s growth, helping it develop properly. 

But, what about crystalwort that grows on the surface of water? Well, this type of Riccia fluitans receives carbon dioxide from the air above.

Therefore, it can photosynthesize naturally with no need of any injections. 



By adding fertilizers to your crystalwort, you can impact its development and growth. This is especially true if it absorbs nutrients through its leaves.

Riccia fluitans can benefit from liquid plant fertilizers. You can add this straight into the water column. If the water column remains low, your plant will typically stay pretty skinny.

To see the biggest impact on the plant’s mass and health, you should use plant fertilizer with macro and micronutrients. 

Growing Crystalwort In An Aquarium – How To Guide

When laying crystalwort in your tank, you need to follow the same process as you would with any other tank plant. Firstly, you need to select a space in the tank where you want the plant to grow.

You have a few options here – on the tanks, bottom, its walls, on rocks or driftwood, or have it floating on the surface.

The method for growing crystalwort depends on where you want to grow it.

Crystalwort Wall

Crystalwort can be easily and quickly grown as a wall. Simply pin it to your tank’s side using a plastic mesh or net, and this will keep it firmly in place.

As time ticks on, the plant will continue to grow around and over the netting. The final result will be a full, grassy wall.

Crystalwort Carpet

Again, growing a crystalwort carpet is pretty straightforward. You just need to use a couple of pieces of plastic mesh and place your crystalwort plant between these pieces.

Then, tie them together using a string or a fishing line. Over time, the plant will grow over the plastic mesh until the mesh is out of sight.

The final result is a lush, bright green carpet that glistens from within your tank.

Crystalwort On Driftwood

It may not be as easy as the two previous methods, but growing crystalwort on driftwood is somewhat simple, too.

All you need to do is tie some pieces of the plant to the driftwood with a fishing line and submerge it in your tank’s water.

Before long, the piece of wood will be completely covered in bright green crystalwort. 

Floating Crystalwort

Riccia fluitans has a mind of its own! So, if you don’t tie it down to something, it will simply float around the surface of your aquarium.

This is because they do not grow roots, as many other plants do. Leave your crystalwort long enough, and it may grow out of the top of your tank! 

Immersed Crystalwort 

When immersed in water, crystalwort tends to grow extremely well. But, as long as some of it remains in the water and it receives some light, it will continue to grow unimpeded. 

Compared to being fully submerged, crystalwort that is just immersed does not require as much care and will grow more easily.

Furthermore, it will not need any additional C2 injections to help promote growth, either. 

Crystalwort Propagation 

To propagate crystalwort is easy in any tank environment. Most of the time, it will even propagate without any outside help by releasing spores from its stem’s tips.

These will then float around the tank and grow new branches elsewhere.

However, you can help the process along by cutting off a few branches of the parent crystalwort so they begin to grow brand-new plants.

The Dry Start Method

Experienced aquarists may be familiar with the dry start method. This provides an unlimited amount of Co2 to your tank and crystalwort without needing to purchase anything.

This method helps your plant grow healthily and properly.

The method looks something like this:

  1. Only add enough water so that it reaches the surface where the lowest part of the substrate is. This is instead of filling the tank fully with water immediately after planting. 
  2. Now, place your crystalwort on top of your substrate.
  3. Using cling film wrap, cover the tank’s top completely. This will increase the tank’s humidity.
  4. After 3 to 6 weeks, you can proceed with flooding the tank.

Before long, your crystalwort will begin to thrive and grow happily in your aquarium.

In Summary

Crystalwort, or Riccia fluitans, is a welcome addition to many aquariums. With its lush green cushioning, crystalwort can not only look great in a tank but it can also make the whole environment healthier.

Best of all, it is affordable to buy and easy to grow and take care of. 

Whether you want to cultivate a carpet of crystalwort or have it form walls in your tank, its dense mat will be beneficial to many species of fish.

Because crystalwort absorbs nitrates in the tank’s water, it serves as a great breeding spot for different species of fish.
Jose Viacrucis