Riccia Fluitans/Moss Mats – Fishing Line and plastic grid/cloth method

There are many different methods to create flat sections of moss, riccia, or other plant life that doesn’t typically carpet or grow in such a form naturally. These mats can be quite effective when fully grown, and allow the easy control and use of new colors and textures in the planted tank. Takashi Amano is credited with first using riccia fluitans, aka crystalwort, in such a scenario. Since, many different types of plants have been experimented with, some with more success than others. Here’s what you’ll need to make a mat:

The Plant

Mats work best with fast growing species that split in many different directions as they grow.  Common choices include Riccia fluitans/ CrystalwortJava MossChristmas MossPellia liverwort (Monosolenium tenerum), or Fissidens.

The Mat Material

Any material which can withstand being under water without decay or contaminating the water (many plastics, stainless steel 316, etc) can bee used for this. Common choices include nylon netting from craft stores, plastic grids from craft or hardware stores, metal meshes, or re-used material from bath poofs, filter media bags,… The material needs many openings that are large enough to let in light and allow the plant to grow through while being small enough to hold back the initial portion of the plant. Be careful if using metal – stainless steel 316 is the most common choice for fish tank use, and those edges can be sharp!!


Any string or thin material that won’t degrade under water that can fit through the holes of the chosen material works for this step. Fishing line is a common choice, as it is hard to see and easy to use. The thinner the line, the less visible and easier to work with. Riccia Line is usually just a green tinted fishing line, such that it blends in quite well immediately. Nylon thread also works well for this and is available in a variety of colors. If you steel mesh for the material and attaching the mat directly to wood or an object, then thread or line won’t usually be needed.

My riccia and moss mat process using filter media bag and fishing line:

Collect the portions of riccia, moss, etc to be used and plan out the size of the mat. The plant will need to be placed between two layers of the mat material, so either cut two identical pieces for the top and bottom, else, if the material is easily folded, cut a single piece that can be folded to give the right mat shape. Giving yourself some extra room around the edges that can be trimmed can make sewing together the mat easier.

Spread the plant portion over the mat material that will form the bottom half of the mat, as below.

A uniform layer just thick enough to cover the entire mat bottom is ideal. If the layer is too thick, portions of the plant often die or decay due to lack of light and water flow. Put the top half of the mat into place, and use the thread/line to tie small knots every half inch or more along the open edges.

I keep the mat wet with tank water throughout the process. Any sections of the plant that dry out can become damaged and die rather than grow into the mat.

I’ll be sure to post updates soon on how these mats are growing out in my new 7 gallon setup! I also ordered some stainless steel 316 wire mesh/screening this week, and will be making some mat portions with that as well. I’ll post on it once I’ve found a good method.

Handling Online Plant Orders

I’ve ordered many of my plants online, though I try to buy from my LFS (local fish store) when possible. Most reputable online sellers have good quality plants, usually prepared well before being shipped. This means that the plants have been cut, unhealthy parts trimmed, and arranged nicely in packaging. Buying from individual planted tank enthusiasts, such as through Ebay, Aquabid, or forums, results in inconsistent preparation of the plants.

Preparing to plant

Prepared to plant!

The first time I received an unprepared plant order, my first impulse was to become angry with the seller and document how horrible everything looked. As I picked through the plants more thoroughly to take photos, it became clear that the plants weren’t dead – they were just ugly, overgrown, and tangled. While orders like these definitely take significant time and effort to prepare properly, they can often yield large numbers of plants for a low cost.

Here are some shots from an order I received mid January through Aquabid. I had ordered previously from this seller, offering a large number of plants for quite a low price. The first order was beautiful and, save for a stuffed box of ludwigia I’d gotten for a steal, everything was well trimmed and prepared. The second order, however, contained many tangled masses of unprepared plants.

A tangled mess of ludwigia

A tangled mess of ludwigia

Each stem had to be pulled apart, with dead leaves or stem portions cut off. Some stems were alive with many roots but without any leaves. In the end, I had a large pile of trimmed, usable ludwigia alongside a pile of salvageable waste.

The cleaned pieces could then easily be bundled and held by anchors. It’s important not to wrap the plant anchors too tightly around or cause breakage in the stems. Then, the bundle can easily be planted.

Here was the tank after cleaning and planting all of the order:

My Riccia Fluitans Nightmare


Riccia Fluitans, commonly known as Crystalwort, can be an absolutely gorgeous plant. I first came across it when purchasing red cherry shrimp and water sprite from a craigslist advert. The guy who posted the advert was a local fish enthusiast with many freshwater plants for sale as well. We wound up chatting for a while about plants, shrimp, fish, tips and tricks. He recommended I try giving Crystalwort a chance, saying it could be floated or tied down. I left with a decent golf ball sized portion in addition to everything else I planned to get.

Here was the tank before I added any of the extra plants. The first plant species added was HC Cuba, which did quite well given the lighting, Flourish Excel, and Ferts I began adding. The HC began to quickly spread, and the sword and crypts I later added also took off. Yet, the tank was still rather bare, prompting me to look into some taller plants. This was were I thought water sprite might be a nice addition as it can grow quite tall very quickly, giving the bettas more hiding spots while utilizing more of the tank space.

I tied the riccia down to rocks with green nylon thread (worked okay, but fishing line works much better!), and placed the rocks throughout the tank where desired. Soon, the riccia had begun to grow in beautifully.

The main planted floor

The main planted floor – Riccia and HC Cuba clearly separated

Riccia circled in blue and HC Cuba in yellow

Riccia circled in blue and HC Cuba in yellow


Here are some huge mistakes I made in “maintaining” this tank, which led to crystalwort becoming a huge issue rather than a beautiful plant.

  1. Turn off filters and powerheads while trimming crystalwort! This stops the trimmings from becoming caught in other plants and eventually growing.
  2. Remove small trimmings immediately. Allowing the riccia trimmings to float ended in disaster. I had hoped they would grow more as floaters, then could be turned into more tied down sections. Instead, the trimming continuously got caught in other plants, like my HC.
  3. Pick out stray pieces frequently. Regular checking of the HC Cuba to remove any bits of crystalwort would have saved my HC carpet. Instead, I let the riccia continue growing. Crystalwort can easily choke out HC in good growing conditions, which is what began to happen in my tank.


Here is my tank once the riccia really began to take hold. By this point, the HC Cuba had begun to suffer terribly, being starved out and losing light.

Once it became clear that I needed to intervene, there didn’t seem to be many options to separate the crystalwort from the HC Cuba. I had to pull out the entire mat, separating pieces by hand. The carpet was replanted and the riccia moved to another tank. I had two successive tragedies with faulty CO2 gas regulators and overdosing fertilizers that ultimately destroyed my HC Carpet in this tank. I’m planning new foreground plants, and perhaps giving HC Cuba another try soon though!