Pike cichlids of the genus Crenicichla make very interesting and challenging aquarium residents. The following article is a brief introduction to this genus of South American cichlids.
Pike Cichlids are a group of South American fishes of the genus Crenicichla.
They inhabit the freshwaters lakes, streams, rivers and pools of most of the
Amazonian rivers, but there are many species found in Colombian, Venezuelan
and Guyanan waters to the north of the Amazon. To the south, there are representatives
of the genus all the way down to coastal regions of central Argentina. Basically,
they are found east of the Andes, from the island of Trinidad in the north to
the area around the Argentinian Rio Negro just north of Patagonia.
These fish are predominantly warm water fishes, with a few notable exceptions
such as Crenicichla lacustris of Argentina and Crenicichla scotti
of Uruguay. Crenicichla or Pike cichlids as their name implies, are
mostly predatory, consuming small fish for prey. There are a few exceptions,
as usual, such as Crenicichla compressiceps and C. cyclostoma
from the rapids of Eastern Brazil that are specialized insect eaters.
Most Pike cichlids have an elongated body and a wide, protrusible mouth - features
common to many predatory fish. There are some sedentary Pikes such as C.
jegui that spend most of their time waiting for prey to swim by, at which
time they lunge and grab the hapless fish. Predatory fish vary in their level
of activity. To compare with saltwater fish, Pikes are somewhere between Rockfish
and Barracuda in style and activity. Most Pikes position themselves near sunken
tree stems, rocks and substrate, giving a quick, short but spirited chase to
catch prey. Keeping Pikes in aquaria requires that you remember this fact. Housing
them with fish less than half their size is inviting trouble - driven by instinct,
they will attempt to eat the smaller fish even if the smaller fish cannot be
Pikes come in many sizes. There are manwy dwarf Pikes that don't grow longer
than 3-4 inches. They possess most of the color and interesting behavior of
their larger cousins but remain small enough for aquarists to enjoy without
giving up much floor space for fish tanks. Then, there are many medium-sized
Pikes that reach a maximum size between 6 and 10 inches. And finally, there
are lunkers, growing to 18-24 inches. There is a Pike for everyone. While Pikes
have a reputation worse than that of Central American Cichlasoma sp., for tearing
up other fish and destroying their environment, the truth is not that macabre.
While Central American cichlids sometimes enjoy redecorating their environment,
jaw structures of Pikes are not physiologically equipped to move and pull or
tug. They usually do not dig up plants as much as Cichlasomines.
Aggression can be a problem with Pikes if you are not careful. Use caution
when it comes to choosing tankmates. Most aggression is reserved for members
of the same species; choosing tankmates of the same size can minimize this kind
(conspecific) of aggression. Housing them with species of different shape and
color can reduce aggression with other species. When all else fails, it's time
for PVC. Addition of PVC tube sections wide enough to comfortably fit the Pikes
into, seems to reduce aggression tremendously. I always make sure there are
more PVC tubes than Pikes. Species that can't stand the sight of each other
often will coexist in a tank furnished with numerous PVC tubes. Of course, these
tubes are not exactly natural or attractive but they are sometimes the only
way out. If you can find similar hollow pieces of driftwood, you can have aesthetics
Tank size for Pikes is largely dependent on the maximum size of the particular
fish. Dwarf species like C. notophthalmus, C. regani and C.
urosema can be kept in tanks as small as 30 gallons. Some dwarves like
C. compressiceps, while remaining small, are fairly aggressive and
need more room - I wouldn't keep them in anything smaller than a 55-gal. tank.
Slightly bigger but relatively peaceful species like C. cf. menesezi,
C. geayi and C. britskii can be maintained in 55-gal. tanks.
Most of the rest require tanks in the 75 to 125 gals. range. Large species like
C. johanna, C. lugubris and Orange Pikes (C. sp.
Xingu I) need 125-gal. or larger to exhibit their normal repertoire of behavior.
I usually purchase fish that can be raised in a 55 or 240 gal. tanks since those
are the sizes of tanks I have available. While raising Dwarf Pikes in a larger-than-necessary
tank may seem excessive, it is very rewarding - they exhibit natural behavior
that you'd never see in small tanks.
Water quality is usually not a critical issue for the medium-sized, spangled
Pikes of the saxatilis-group; they are hardy and can happily live and breed
in most treated tap water. The same goes for the Froghead Pikes formerly known
as Batrachops. The large, small-scaled Pikes of the lugubris-group and the dwarf
species need better water quality, since they are usually found in low-pollution,
low-bacteria black waters of the Amazon. A regimen of large, partial water changes
and powerful biological filtration should take care of these fish. Lax water
quality management leads to "hole-in-the-head" disease in some large
Pikes. The dwarves simply die if you don't keep the nitrogen levels in the water
While none of them require soft, acidic water for day-to-day living, the black
water species usually need water with pH and hardness resembling their native
habitat - pH of 5 to 6 and extremely soft to successfully breed. I have spawned
many of the Spangled Pikes in hard, alkaline water but spawning occurred only
with frequent, large water changes.
Feeding Pikes is usually not a problem, tank-raised Pikes happily accept prepared
foods but fish imported from the wild are often difficult to feed - they demand
live or frozen meaty foods. Juveniles imported from the wild can be converted
onto pellets much faster than adults can. Keep in mind that these are predatory
fish and feed them a varied diet frozen crustaceans, fish, live earth worms
and live fish. Even specimens that accept pellets should be fed frozen and live
foods regularly. Feeding a diet lacking in certain unknown minerals has also
been pointed at as being the cause of hole-in-the-head disease. A variety of
foods is key.
Reproduction of Pike cichlids in aquaria, unfortunately, does not occur frequently
enough. It is not because these are difficult to breed, but because so few people
try breeding them. The easiest group to get to spawn in aquaria is the saxatilis-group
(Spangled Pikes). I believe Dwarf Pikes and the giant Pikes of the lugubris-group
are more difficult due to their water requirements (see above). Of course, you
see fry of Dwarf Pikes being offered for sale more often than those of the 'Giants'
do, not because the dwarves are easier to spawn, but because they are easier
to house and provide for due to their sizes.
Breeding lugubris-types requires a fairly large tank (A pair of C. lugubris
belonging to Frank Warzel spawned in a 75-gal. tank but he claims that it is
the smallest tank they'd breed in.) Providing large quantities of soft, acidic
water can be an expensive proposition if you live in an area with hard, alkaline
water. Wayne Leibel spawned, C. marmorata in a 150-gal. tank. As far
as I know, he's the only American to have succeeded in breeding any of the lugubris-group.
I believe that if enough people make an effort at proving the space, water-quality
and dietary requirements of these large Pikes there'd be many more breeding
reports. C. lugubris, C. marmorata and C. vittata
are the only large Pikes that have been spawned (to the best of my knowledge)
in aquaria. The laying of eggs without successful hatching of fry has been reported
in C. phaiospilus, C. sp. Xingu I and C. acutirostris.
Pikes are cave-spawners, laying their adhesive eggs somewhere where it would
be difficult for you to see. The female is responsible for the care of eggs
and the male guards the immediate region against intruders. The eggs hatch in
about 3-4 days and the fry are free-swimming in another 3-4 days, depending
on the temperature. The fry are fairly large and can be fed newly hatched brine
shrimp as their first food. Fry growth is very fast and if not segregated by
size, the resulting cannibalism can lead to a highly biased sex ratio in some
species, particularly in the saxatilis group. □
Leibel, W. S. 1992. "The Marbled Pike Cichlid," Crenicichla marmorata Pellegrin 1904. Cichlid News Vol. 1 No. 2.