TOP LEFT & BOTTOM: HANS-GEORG EVERS; TOP RIGHT: SUMMER RAYNE OAKESAMAZONAS
Mass of Marimo Lake Balls
in an import facility.Mid-size Marimo Balls showing bubbles
of oxygen they produce in the aquarium.of an LED lamp, a healthy planted vase can express every
bit of the photosynthetic radiance of a more ambitious
aquascape, while demanding less effort and easily fitting
on a desktop or kitchen counter. Aquarium mosses, An-
ubias, and Microsorum Java Fern are all fitting selections
for a glass vase aquascape, and Marimo Balls are another
excellent low-tech choice. According to the modest care
demands of Marimo Balls, the water in the vase should
be changed every few weeks. Conditioned tap water from
most areas will probably suit the Marimo Balls well and
provide the extra calcium that favors their growth and
vigor. Fertilizer dosing and vase-suitable animals, such
as one or two Cherry Shrimp or, for larger containers, a
single fancy Platy or Guppy, will provide other nutrients.
Avoid excess growth of nuisance algae—the downfall
of many wild Marimo Ball populations—by stocking
animals and fertilizing lightly. Before each water change,
remove the Marimo Balls and shake and squeeze them in
a separate water-filled container. Reshuffle them when
replacing them in the vase. These simple extra steps will
mimic natural wave action and help the Marimo Balls
to maintain their spherical shape and shed detritus that
settles in their filaments.
It is easy enough to add a few Marimo Balls to a
traditional low-tech or high-tech planted aquascape.Average aquarium param-
eters favorable for other
aquatic plants will also
support Marimo Balls, and
a few in the foreground of
a planted layout can make
an eye-catching counter-
point to other plants with
varied textures and colors.
Nevertheless, the special
growth habits and ecology
of the wild A. linnaei hint
at ideas for other unique
planted systems.
Aquarists have some-
times encouraged, or tem-
porarily admired, the dense
growth of Black Brush
Algae (Audouninella sp. and
other Rhodophyta) that can develop on stones and drift-
wood, but A. linnaei presents opportunities for intentional
algae-scapes. With some luck, pieces of mat torn from a
few sacrificed Marimo Balls might adhere to hard surfaces
after attachment with thread or cyanoacrylate glue and
grow to cover the surface with a solid green turf like the
attached form in nature.
The special wild habitats of the ball form of A. linnaei
suggest yet another unique biotope option. In a system
energized with a controllable reef tank wavemaker and
decorated with a simple sandy bottom, Marimo Balls
should roll about as they do in their natural habitats. A
setup like this in a roomy enclosure, further equipped
with good lighting and CO 2 injection, should grow Ma-
rimo Balls very well. If maintained for a couple of years
in favorable aquarium conditions like this, Marimos
will probably put on measurable diameter and develop
smooth spherical shapes. It would be difficult to track
down the same cyprinids and other small lake fishes that
might share the Marimo Ball habitat in northern Japan
or Northern Europe (Alburnus, Gasterosteus, and Leucis-
cus, among others), but a group of active, silvery aquari-
um fish, such as Fundulus killifishes, small Botia loaches,
or large Danio spp. could further enhance the effect of
a sunny, shallow, wind-tossed bay in a glacial lake alive
with rolling Marimo Balls.REFERENCES
Boedeker, C. and I. Immers. 2009. No more lake balls (Aegagropila linnaei,
Kützing. Cladophorophyceae, Chlorophyta) in the Netherlands? Aquat Ecol
43: 891–902.
Boedeker, C., A. Eggert, A. Immers, and E. Smets. 2010. Global Decline of
and Threats to Aegogropila linnaei, with Special Reference to the Lake Ball
Habit. BioScience 60: 187–98.
Tagashi, T., H. Sasaki, and J. Yoshimura. 2014. A geometrical approach
explains Lake Ball (Marimo) formations in the green alga, Aegagropila
linnaei. Sci Rep 4: 3761.