month we welcome back regular U.K. contributor Chris
Ralph with his insight on the "Iridescent Shark",
Pangasianodon hypophthalmus , and histrepidation on keeping this large catfish in
the home aquarium.
is a catfish which should never be imported due to
the eventual size that it can attain, and the fact
that it is a very nervous and skittish fish, which
does not fare well in the confines of cramped aquaria.
All too often this catfish is offered for sale as
a juvenile fish at around 75-100mm and is quite often
labelled as Pangasius sutchi or Iridescent
A couple of years ago whilst
on a day out with Kate looking at some aquatic retailers
we were horrified to find that this catfish was
being offered as the fish of the week on a buy one
get one free basis. Needless to say we shall not
be venturing back to that retailer. If only these
catfish remained small and manageable, but alas
they do not.
These catfish are bred commercially
in large ponds for the aquarium trade, which begs
the question why? Obviously there is a demand or
else this trade would not exist, how we control
the importation of these fish is another story!
Who in their right mind would want to keep a catfish
that is capable of weighing in excess of 44kg?
is also an albino form of this catfish which is
also offered for sale. It is documented that this
is a migratory species of catfish moving upstream
to spawn in May-July. This fish has been introduced
to other countries other than those documented below
which include Bangladesh, Philippines, Singapore
size would need to be as large as possible but as
an absolute minimum for a 450mm specimen I would
suggest a 72” x 24” x 24” aquarium,
even though I do not advocate the keeping of these
the Mekong, Chao Phyra and perhaps Mekong basins;
Thailand, Laos, Cambodia and Viet Nam. It is documented
that this catfish has been introduced into additional
river basins for the purposes of aquaculture.
1300mm or 52” SL (standard
length is the measurement from the tip of the snout
to the base of the caudal peduncle).
The ideal temperature range
The ideal range is 6.5-7.5
The body is best described
as being elongated. The position of the mouth is described
as being terminal. There are 6 branched dorsal fin
rays and the pelvic fins have 8-9 soft rays. The gill
rakers are described as being normally developed,
with small gill rakers being interspersed with larger
The fins of this catfish are
dark grey or black in colour. Juvenile specimens are
described as having a black stripe along the lateral
line with a second long black stripe below the lateral
line. Adult fish are described as being uniformly
grey in colour. These catfish have a dark stripe on
the middle of the anal fin and a dark stripe in each
of the caudal lobes.
Care & Compatibility
Whilst this catfish is fairly
peaceful avoid keeping it with small fish as they
will eventually appear on the menu. It is best to
keep this catfish with other large fish avoiding those
species that are too boisterous.
There are no known
records of aquarium spawnings of this catfish, which
is most likely due to the adult size of these fish
and the enormous size of aquarium required. To be
honest it is quite a relief that these fish have not
been bred in aquarium conditions.
It is documented that the males
have darker stripes and are more slender than the females.
This catfish is best described
as being an omnivore feeding on a mixed and varied
diet that includes catfish pellets, catfish tablets,
frozen bloodworm, floating food sticks and vegetable
matter to name but a few.
on the upper portion of the gill arches. Lateral Line: A sensory line, along
the sides of the body.
Pangasianodon: Pangasius +
an (Greek for without)+odon (Greek for tooth); in
reference to the toothless state of the adult fish. hypophthalmus: With an eye-spot
H.A. and R. Riehl 1985 Aquarien atlas. Band
2. Mergus, Verlag für Natur- und Heimtierkunde
GmbH, Melle, Germany. 1216 p.
Catfish Association Great Britain Volume
1. FishBase - www.fishbase.org.
Planet Catfish - www.planetcatfish.com. Published
in Practical Fishkeeping
ScotCat – www.scotcat.com.