Page 373 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

OXYGENATORS 371

Utricularia vulgaris Ceratophyllum demersum
Common Bladderwort Hornwort root, but if in contact with a substrate, the leaves
will start to anchor the plant in place. Over the
ORIGINS Widely distributed in temperate parts of ORIGINS May have originated in Asia, but now occurs course of the growing period, hornwort forms
Europe, Asia, and North America. throughout temperate regions of the world. long strands. As the leaves start to die back, the
SIZE Stems reach 6 to 18 in (15–45 cm) in length. SIZE Stalks may reach up to 24 in (60 cm) in length. budlike tips of the strands drop off (or can be
WATER Prefers relatively calm water in a sunny position. WATER Not fussy about water chemistry; grows well in cut off) and sink to the bottom of the pond, and
Hardy to –30°F (–34°C). both sun and shade. Hardy to –10°F (23°C). it is from these buds that new plants will develop
PROPAGATION Remove young plantlets from an PROPAGATION Break up the stems of established plants the following spring. By the end of the growing
established plant during the growing season. during the growing season. season, Hornwort becomes very straggly, so it is
best to pull out the plants at this stage. Hornwort
The unusual name of this plant originates from the is strictly aquatic and dies back if exposed to the
distinctive broad shape of its growing tip, which is air for any length of time. It is also fragile, and
reminiscent of a cow’s horn. Hornworts do not breaks easily when handled.

This slow-growing, rootless carnivorous plant has
bladderlike structures among its foliage; as well
as providing buoyancy, they also trap tiny aquatic
creatures, including newly hatched fry. In summer,
it produces a cluster of yellow flowers held above
the water on a strong stem. Bladderwort may
become choked by blanketweed (see p.319).

Fontinalis antipyretica Hottonia palustris
Willow Moss Water Violet

ORIGINS Widely distributed in parts of Europe, Asia, ORIGINS Found naturally in the wild throughout
North Africa, and North America. much of Europe.
SIZE Stems can grow to a length of 20 in (50 cm). SIZE Can grow to a height of more than 3 ft (1 m).
WATER Prefers clear water, but tolerates either sun or WATER Thrives best under acidic water conditions with a
shade. Hardy to –30°F (–34°C). pH of 6.0–6.5. Hardy to –20°F (–29°C).
PROPAGATION Break off branches from established PROPAGATION Divide clumps during the growing
plants and attach them to submerged objects. season, or take cuttings.
Although this hardy moss does not flower, it Despite its name, this plant is not related to the
has an attractive appearance. It fares best violet but actually belongs to the primrose family.
in ponds free of filamentous algae and The large surface area of Water Violet’s fine
is particularly suited to areas around foliage makes it a valuable oxygenator.
waterfalls, since it naturally During summer, plants develop flower spikes that
occurs in fast-flowing stand more than 12 in (30 cm) above the water’s
streams. Willow Moss surface. The leaves on the flower spikes are more
will attach itself by its compact than the fine, feathery foliage that Water
roots to submerged Violet displays on its submerged parts. The flower
objects, such as planting color itself can be quite variable, ranging from
containers and rocks. white through pinkish-lilac to blue. As the flowers
Hold pieces in place fade, the flower stems falls back into the water,
with a rubber band and the seedheads develop. Water Violet dies
until the roots get back naturally in the fall, when the plants form
a firm grip. so-called winter buds, or turions, from which
new plants will grow again the following spring.
Leaves vary in Although Water Violet is hardy, it tends to thrive
color from green only in clear water, and it will be adversely affected
to olive-brown
by any buildup of filamentous algae in the pond.

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