Questions
Answers
Questions
Answers
Questions
Answers
Questions
&
with David Wolfenden
Getting the
Goat?
I’ve seen goatfi sh for
sale in my LFS - are
they good sand sifters
for the reef aquarium?Stirring the substrate
of the aquarium helps
to dislodge detritus
and mulm, as well as
helping to clear cyanobacteria
and diatoms which may settle
on the sand. Whilst aquarists
maintaining deep sand beds
often discourage disturbance
of the substrate, some form
of stirring is benefi cial in
relatively shallow. Goatfi sh
can be excellent at performing
this janitorial duty in the right
setup, but they aren’t suitable
for a lot of systems on a long-
term basis, and you’ll need to
weigh up how they will fi t into
yours.
There are many species of
goatfi sh, but there are two
species from the Indo-Pacifi c
which are commonly imported
and seen in the trade. The
bicolour goatfi sh (Parupeneus
barberinoides) is a very
attractive species, with a red
anterior and yellow posterior
half – this goatfi sh reaches
some 20cm in length. Yellow
goatfi sh (P. cyclostoma) exhibit
bright gold coloration as
juveniles, although adults tend
to dull with age and there areQ
A
also varying colour morphs -
this species reaches 30cm or
more in length.
Goatfi sh sift through the
substrate in search of worms,
copepods and other fauna
(assisted by their barbels), and
if you’re looking to maintain an
active, live sand bed this can be
a problem. Even one fi sh can
rapidly deplete the substrate’s
fauna, so do bear in mind
that this may impact on the
sand bed’s diversity. The fl ip
side of this is that the sand is
frequently turned over, detritus
is dislodged, and cyanobacteria
and diatoms are discouraged
from settling. Goatfi sh tend
to require a fairly fi ne sandy
substrate to allow them to
exhibit their natural behaviour;
a mix of diff erent grain sizes
can work well, but excessively
large gravel or rubble chunks as
the predominant substrate are
not suitable.
A goatfi sh is unlikely to meetits nutritional needs from a
typical sand bed alone, and
frequent supplementary
feeding will be necessary.
Bear in mind that these fi sh
will predate on smaller fi sh
tankmates, and ornamental
crustaceans are also fair game –
as the goatfi sh grows, they will
tend to be more destructive.
The adult size of goatfi sh
presents another challenge- they’re usually imported
at a small size, but they can
grow quickly if the conditions
are right. In this regard, the
bicolour is the most suitable for
the typical reef aquarium due
to its relatively small size, but
you’re still looking at 500 litres
or so for one individual with an
ample sand bed area – a yellow
goatfi sh will need even more
than this.
On balance, goatfi sh are
excellent if you’re looking to
maintain a larger reef system
with robust fi sh tankmates and
you’re not intending to keep
ornamental crustaceans. For
the nano system, and for those
housing shrimps and smaller
fi sh, they’re best avoided.Threat of
Invasion
I love the look of puls-
ing xenia – but I don’t
want it taking over my
tank. Are there any
ways to keep it in check?Pulsing xenia
(Xenia elongata)
is mesmerising to
watch, and a tank
full of this stuff can look
amazing! In fact, a dedicated
species-only Xenia tank can
look stunning. Obviously
that’s not everyone’s cup of
tea, and it has a reputation for
weed-like growth, so you’re
quite right to be thinking about
stopping it from taking over- given the chance, Xenia will
overgrow and smother corals.
There is also the possibility
of allelopathic ‘chemical
warfare’ aff ecting other sessile
invertebrates if it’s allowed to
grow rampant (although the
toxins the Xenia produces may
be adsorbed to an extent by
activated carbon).
There is no sure-fi re way to
prevent a Xenia takeover as
it is extremely hardy and can
The yellow goatfi sh is very attractive as a juvenile, but can reach a large size. Q
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