Yellow-headed sleeper gobies Valenciennea strigata require a well-established sandbed to provide
enough microfauna for them to survive.
as sand-sifters, and some of them have
a much better record of surviving and
thriving in captivity. Two species in
particular come to mind here: the brown-barred goby Amblygobius phalaena and
the decorated goby Istigobius decoratus.
A. phalaena, which reaches approximately
6 inches in maximum length, gets its
common name from its attractive brown
vertical bars that overlay a golden-yellow
base coloration. The head of this handsome
species is adorned with orange spots and
light blue dashes.
With its light sandy color overlain with
a matrix of orange and black dashes, I.
decoratus blends in remarkably well against
the sandy substrates on which it is naturally
found. Slightly smaller than A. phalaena in
adult length, I. decoratus reaches about 5
inches at maturity.
Unlike the sleeper gobies, both of
these species readily adapt to non-living
meaty foods, so their survival in the
aquarium is far less tenuous. They also
have smaller mouths and tend to limit
their sifting activities to the top layer
of sand, which is less likely to lead to
rockwork avalanches or to interfere with
colonies of denitrifying bacteria.
In larger marine aquariums (200 gallons
or more) with plenty of open sand, one of
the various goatfish species, family Mullidae,
can help to provide the sand-sifting services.
Easily identified by their characteristic
streamlined shape, twin dorsal fins, and
sensory barbels hanging from their chins,
the goatfishes continually grub through the
sand in search of buried prey.
The brown-barred goby Amblygobius phalaena.
wardii, and the long-finned sleeper goby
One drawback to the sifting behavior of
sleeping gobies is that they tend to delve
fairly deep into the substrate, which can
undermine the rockwork and cause rocks to
shift or tumble. To prevent this problem, you
can insert short sections of PVC pipe into
the sand in a vertical orientation beneath
the rocks. If you cut the sections so they’re
no taller than the sand is deep, they’ll be
undetectable to the casual observer.
Digging too deep can also disturb the
colonies of denitrifying bacteria deep
within the sandbed, thereby interfering
with natural nitrate reduction—the main
reason many aquarists choose to use a DSB
in the first place.
Once while I was diving with a friend on
his live rock aquaculture site in the Florida
Keys, we noticed that our activities were
being watched closely by a pair of yellow
goatfish Mulloidichthys martinicus. We were
digging up rocks that had been buried in
the sand after a recent hurricane and were
stirring up quite a bit of sand in the process.
I suspected they were waiting close by to
snatch up anything edible that we might
have unearthed. But then again, perhaps
they were just amused at the sight of two
clumsy, bubble-blowing humans poking
around the ocean floor with potato forks.
In addition to the sleeper gobies, there are
other goby species with a solid reputation
As I’ve already indicated, the goatfishes
get fairly large, most topping out at around
a foot in length (and some even exceeding
that), and they’ve got an appetite to match.