My Green Wet Thumb: Merry Christmas (Moss) by Derek Tustin Even though I have been interested in aquatic plants for a number of years, one area that I have never really delved into is the various aquatic mosses. I’ve kept Java Moss (Vesicularia dubyana) in the past because it was a hitchhiker on something else I had purchased, but have never gone out of my way to acquire any others. However, I was recently looking at the on-line plant list from Menagerie Pet Shop, and noticed that an entire section has been added for aquatic mosses. I decided to do a bit of reading, and as a result came across what I think is the perfect plant as part of a written Christmas gift to you all… Aquatic mosses are small plants with small, closely overlapping leaves and very delicate stems. They never produce flowers, are most often found growing attached to rocks in streams, but can sometimes be found in other aquatic locations. There is a degree of confusion about the exact scientific name for many of the aquatic mosses, and therefore many are sold almost exclusively by their common names. For instance, Java Moss is often known as Vesicularia dubyana, but some argue that the true scientific name should be Taxiphyllum barbieri. This confusion extends to the plant I am writing about this month, Christmas Moss. It is most often referred to as Vesicularia montagnei, but is also sometimes referred to as Vesicularia dubyana var. abbreviate. It appears that this lack of definitive scientific description arises from the fact that the various aquatic mosses grow in subtly different forms under different conditions which in turn hampers an accurate identification. Christmas Moss is a relatively new addition to the aquatic mosses available for purchase, with it first being reported for sale in Singapore around 1998. Apparently one specific local fish store had several tanks set up with a new and different moss. The store (who claimed that they had brought the new aquatic moss themselves from Taiwan) refused to sell it separately, insisting instead that it had to be purchased as part of an entire tank set-up. Now the store was selling those set-ups for several thousand Singapore Dollars. (The Singapore Dollar is and was a strong currency. In 1998 the exchange ratio was 1.00 SGD = 0.838776 CDN, so in 1998, $3,000 Singapore Dollars would have equated to about $3,575 Canadian Dollars.) As you can appreciate, this was a hefty price to pay to acquire a sample of a new aquatic moss. One respected aquarist in Singapore, Loh Kwek Leong (also the owner and operator of www.killies.com) recounts that he was the one to give the newly introduced aquatic moss its name. The story goes that when he first saw the aquatic moss, the store in question was referring to it as Taiwan Moss or Triangular Moss, but he never paid attention to nor remembered those names. He tried to convince the store to sell him some, but they adamantly refused. As we aquatic hobbyists are wont to do, he was talking to one of his hobbyist friends, and had asked if he knew where Loh Kwek Leong could acquire some of this new aquatic moss. His friend didn’t know what he was talking about so Loh Kwek Leong, not remembering the names the store was selling the aquatic moss under, described it in detail. At which point the friend said “Oh, you mean the moss that looks like a Christmas Tree.” Loh Kwek Leong’s friend was fairly accurate in his description. When grown under optimal conditions, the mature fronds take on a very triangular shape and this, combined with how they overhang each other like the boughs of a Christmas Tree, provided the common name. Loh Kwek Leong eventually obtained some of the moss in question as a contaminant on some ordinary Java Moss and became the foremost authority and propagator of it. He was also a close friend of the publisher of the Singapore local version of the Aqua Journal. (Aqua Journal is a Japanese publication. Around 2000 they apparently attempted an English version in conjunction with a company called Vectrapoint in Singapore, but the venture quickly folded.) He and the publisher were talking about the new moss, and Loh Kwek Leong referred to it as “Christmas Moss”, and that name subsequently appeared in an article in volume 38 of Aqua Journal. For those of you not familiar with aquatic mosses, they serve a variety of uses in an aquarium. First and foremost is decoration. They can be tied to other decorations (driftwood or rocks for example), and they quickly grow to cover the object in question. Another utilization is for it to be left floating as a spawning site for egg-laying species, or as a refuge for the associated fry. The most recent use is to let it grow (either immersed or emersed) to form a moss wall. – Page 30 Tank Talk December 2011 / Volume 39, Number 04 Christmas Moss is something of a mystery in the hobby. While its exact geographic origin is not known, it is believed to have initially gathered somewhere in Taiwan, although some sources indicate that it is native to Brazil. The consensus seems to be that in its natural habitat it grows in areas of high humidity along streams and creeks, such as waterfalls or areas where there is a lot of spray. It will grow on the banks of streams and creeks (in both areas of low and high turbidity), as well as on we shaded ground in the surrounding forest. It will grow in substantially different forms depending on environmental conditions. It is recommended that for ideal growth it be attached to either driftwood or rocks and provided with higher light conditions. If grown in this method, the triangular shape of the fronds will become more pronounced. It will also grow readily in shaded areas of a tank, but without a higher light level it is reported that the shape will more closely resemble Java moss, losing the triangular shape in favor of a more stringy appearance. It is also not recommended that you allow the plant to grow on the substrate as a ground cover as it will tend to accumulate mulm and other debris, possibly resulting in an algae bloom in that location. If grown totally emersed, the triangular shape of the fronds will completely disappear, and it will look almost identical to a variety of other emersed grown aquatic mosses. In relation to temperature, it is recommended that you keep Christmas Moss between 24 and 29 degrees Celsius (75 to 84 degrees Fahrenheit), with best growth being reported towards the lower end of the range. Lighting can range from low to high, with the higher end of the spectrum resulting in better growth. CO2 addition is beneficial, but not essential. Fertilization is also beneficial, but again not essential. Finally, pH can range from 5.0 up to 7.5, but the preferred range appears to be around 7.0. In short, if you provide bright light, CO2, fertilization, a temperature around 25°C (77°F), and a pH around 7.0 you will get the best growth. But even outside these parameters, the plant will grow and flourish for you. If you want to learn more about Christmas Moss specifically and other aquatic mosses in general, I would suggest that you visit www.aquamoss.net. While not the fanciest or largest aquatic plant website around, it does provide some insight into the majority of aquatic mosses currently available in the hobby. So there you have it. With the words “Merry Christmas” and the best wishes towards you and yours for the holiday season, I gift to you a bit of knowledge about Christmas Moss! Species Profile Latin Name: Vesicularia montagnei or Vesicularia dubyana var. abbreviate Common Names: Christmas Moss Height: 2.5cm (1”) Light: low – high Temperature: 24°C – 29°C (75°F – 84°F) PH: 5.0 – 7.5 Growth: slow Difficulty: easy Origins: Taiwan or Brazil Source: Various – Page 31 Tank Talk December 2011 / Volume 39, Number 04 .