Import Report
Subwassertang Lomariopsis lineata
Subwassertang is one of the most unusual plants used in aquariums
today. It was apparently first introduced to the hobby in Germany
and given the name Sußwassertang [suss-wasser-tang] for “freshwater
seaweed,” which got mistransliterated as subwassertang with a “b”
rather than the double “s.” The plant grows attached to wood or rock in
tight clusters, similar to moss or liverwort. It has no roots or stems but
roundish-shaped leaves that clump together. It reminds me of the bedding
in Easter egg baskets. Subwassertang grows easily in the aquarium.
What makes it so unusual is it is not really an aquatic plant. In fact, it is
not a fully developed plant at all. Some plants’ life cycles include different
growth forms at various stages. Terrestrial ferns have an interesting
cycle that includes spores, gametophytes, and sporophytes. In a way, a
gametophyte is like the larval stage of an insect, which looks entirely
different from the adult form. Subwassertang is actually the gametophyte
stage of the tree-climbing fern Lomariopsis lineata.
Gametophytes normally have both male and female organs that
produce eggs and sperm that unite to create the next growth cycle
form, but for some unknown reason this gametophyte, which has been
cultivated for the aquarium, is missing the female sex organs and, as a
result, will never transform to the next growth stage and become a fern.
The plant is cultivated in Asian plant farms and has become very popular
in the Singapore and Taiwan markets. It has been exported to Europe and
occasionally to the United States.
From an artistic standpoint, it has great potential and has been added to
the growing list of mosses and liverworts that are highly sought after by
hobbyists. It is easy to grow and maintain. Moderate (or better) light and
well-oxygenated water will encourage the plant to grow and spread, and
higher CO levels will increase the growth rate. With a moderate growth
2
rate, it requires little maintenance and only needs to be occasionally
thinned out. It is a low-profile plant that creates the look of a cushion.
To attach the plant, spread a clump across a rock or a piece of wood
and wrap nylon thread around it a few times. Plastic or metal mesh can
also be used. Be careful not to overdo the netting. Apply just enough to
keep the plant in place.
Needle-Leaf Java Fern Microsorum pteropus
Microsorum, known as Java fern, has been one of the most popular
plants in the hobby for decades. It is often recommended for
aquariums with sub-standard lighting or other less-than-ideal conditions
because of its hardiness and tolerance. In recent years, new variations of this
plant have been discovered and cultivated in Asia. One such variation is
known as the needle-leaf Java fern. The leaves grow long and quite narrow
but arch over and flow freely in the current, unlike some larger narrow-leaf
versions that just grow straight up. It easily attaches to wood and has a
much faster growth rate than other forms of the plant.
Its small stature gives
Robert
HUDSON
the aquascaper more
flexibility in using the
photographs by the author plant for small tanks,
Robert Paul Hudson has been up to dense groups in
an avid hobbyist since childhood
and became interested in aquatic very large aquariums.
plants in the early 1990s.
Inspired by a love of gardening Its ease of keeping is
passed on by his father and the
great encouragement for
writings of Takashi Amano and
Karen Randall, one planted newcomers to the hobby
aquarium grew into dozens. In
1999, he started the website who may otherwise feel
www.aquabotanic.com, first
as an educational tool, and
intimidated by more
then as a business. He enjoys complex plants.
keeping dwarf cichlids and North
American native fish. Robert now Java fern should not
writes for numerous aquarium
magazines and club newsletters, be planted in the gravel.
striving to share his enthusiasm
The roots serve mostly
and love of the hobby.
as anchors to wood and
rock, and if buried the rhizome may eventually rot and kill the plant. Nutrients
are absorbed by the leaves, so regular fertilization to the water column is
needed. To attach the plant, simply wrap nylon thread around the rhizome (the
thick horizontal root portion) to the object in such a way that the plant stands
up straight, or it can be jammed into nooks and crannies.
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www.tfhmagazine.com
August 2009