Later that night, I went down into the fish room.
A flashlight in one hand and a turkey baster in the other…
ready to do the dirty deed!
Dicrossus filamentosa
My trauma in their care and breeding
by Don Maloney
from Wet Pet Gazette, Norwalk Aquarium Society
Aquarticles
Dicrossus filamentosa is a dwarf cichlid found only in northern South America. It
inhabits small, shallow water courses. There are two known populations of D.
filamentosa. One is found in the Orinoco headwaters and the other in the Rio Negro.
The only method of distinction that I’m aware of is two fold: the males of the Rio
Negro morph have a narrow wedge of speckles in the deep fork of the lyre-tailed caudal
fin, and the females develop bright red ventral fins after the first spawn. The other
population’s males have a wide speckled area and their females' ventral fins remain
clear after the first spawn. Regardless of the population this is a beautiful fish with a
striking checkerboard pattern along its flanks. Hence their common name checkerboard
cichlid. Please see the cited reference for an accurate physical description of
this fish. Every major magazine and reference book has at least one decent picture. In
older literature this fish was known as Crenicara filamentosa. Because of the
wide availability of photos I will opt to save valuable paper by not describing this
stunning fish’s appearance. Please forgive me.
I was able to purchase from a breeder/importer out of Massachusetts on 3/20/97.
Researching this fish months before its arrival allowed me to choose carefully the habitat
I would use for its home. I recently purchased a 35 gallon breeder and decided to use it -
its large bottom area making it ideal for small territorial cichlids and shallow water
depth offering excellent light penetration for healthy plant growth and ease of
maintenance. It came without a lid. I easily fashioned one out of 1/8th inch plexi-glass.
For planting this tank I chose Java fern and Java moss and some of the salvinia
sp. floating plants, which were good for a while but began growing out of control. I
can’t tell you how many pounds were pulled out at every water change. Open spaces
between the bunches of Java fern patches allowed the fish free-swimming room. The broad
leaves of the Java fern are absolutely necessary because this fish deposits the eggs on
plant leaves. Coconut shell halves and a small piece of bog wood were in the tank along
with a shale cave for the Apistogramma nijsseni pair which ultimately spawned in
this tank too, at the same time! For substrate I chose fine gravel 1-2" deep for
plant roots, but later began to remove some of it because fine gravel holds too much dirt.
Water that has a low pH value and extremely soft is mandatory in the breeding these
cichlids. The eggs of this species will easily dissolve in even moderately hard water. I
obtain water for these fish two different ways. First, I use rain water collected in a
plastic 55 gallon drum, and second, I use tap water. Both rain and tap water are filtered
through an A.P. tap water purifier. Then it is trickled through peat to produce a water
with a pH of around 5.5-6.0. The water temperature of the new water is slightly cooler
(70F to 72F) than that of the aquarium which is kept at 80F to 82F. The addition of
slightly cooler water definitely aids in triggering the spawning ritual. Water is changed
about 10-15% every 2 weeks.
The fish are fed a variety of foods. This is important as proper conditioning of the
fish insures beautiful, healthy fish and frequent spawns. Frozen foods like bloodworm and
brine shrimp are fed most often because of their relatively high nutritional value and,
most importantly ease of use. I’ll treat them occasionally with live brine shrimp,
and mosquito larvae when they are "in season". When I’m pressed for time
they’ll get Tetra Cichlid flakes. Yes, they’ll take dry flakes! I’ve heard
stories of fish keepers going to extreme lengths to procure all sorts of live and home
made prepared foods for these fish. That was not the case for me.
Filtration is handled by 3 box filters with ceramic noodle, peat, and floss. Filters
are changed when they appear very dirty. The filters are changed on a rotation basis at
water change time.
Lighting is a single 36" plant bulb. The tube is about 12" above water level.
The light is on a timer set for 15 hours. Healthy plants, if you’re going to keep
them, are important because dead and dying plants don’t help keep the water clean.
Change the bulb at least once a year.
The tank mates are 4 Cardinal tetras, 1 pair A. nissjenni, 1 Plecostomus
sp. and 2 Otocentrus cats. Note: I eventually removed the tetras after young filamentosa
fry vanished spawn after spawn. Note on a note: young fry continued to vanish even after
the tetras had been removed! But that’s for later on in the story!
The SPAWNING
The female chooses a leaf on which to spawn. It is usually a perfectly shaped, clean broad
leaf not far from the bottom - about 2-5 inches. She meticulously cleans the leaf. At this
time the female has been doing a lot of head standing when the male comes by. I guess that
is her signal that she is ready to spawn. I never witnessed the blessed event. But in the
morning she is hovering directly over the chosen leaf. The egg mass appears to be about 30
to 50 eggs. I however have never been lucky enough to yield that many fry. She has now
drastically changed her color pattern and attitude. Her normal checkerboard pattern is
replaced with a solid black lateral stripe and her ventral and anal fins have
turned bright red. The male has also lost his checkerboard pattern for the solid black
stripe. She is extremely defensive now, and will move into a headstand position if any
body even looks at her, and she’ll flare her fins and arch her body. If an intruder
gets too close she will dart out at it. After spawning the male receives no better
treatment. He’s chased away and the female cares for the young until they’re old
enough to fend for themselves. I’ve heard stories of severe brutality resulting in a
dead male, but it never came to that with this pair, in my tank. A quick theory as to why:
all the breeding articles that I’ve read that reported male beatings resulting in
death (apistos, too.) had a common denominator - small tanks averaging 15 gallons or less.
Several times I patiently allowed the female to rear the young on her own until
they reached a size when I could take them out. I figured around 1 cm or more. But that
never happened. These fish had spawned numerous times, and numerous times either the
eggs would disappear or the fry would disappear. Only rarely did the fry hatch and hang on
the underside of the leaf for several days, only then to disappear like all the other
times. I didn’t know what was going on, I thought about predation by the neons so out
they came. Sometimes I was fortunate enough to witness the newly hatched fry, clinging to
the underside of the leaf by the tiny suction cup on the top of their heads, be gently
nibbled off by the female and placed in a small depression in the gravel.
Only to be moved every day to a new spot several more times and then, vanish. I had
enough! I had to steal the fry, it was the only way!
Now for the fun part. These fish spawned regularly, They got regular water changes, had
a nice place to live, and got well fed. But, the deal was they lived in luxury and I got
fry. They were not living up to their part of the agreement. So I had to take action,
drastic action! Time to remove the fry. This was not going to be easy because the fry were
not regular free swimming fry. I think the correct word is zygote. You know what a zygote
is. It’s a microscopic fish that is one quarter tail, one quarter eye and half yolk
sac! They were not going to swim into any net! After having watched clutch after clutch
disappear, I knew just when the "rescue" had to be executed. I waited until the
mother took the fry down from the leaf into the first depression in the gravel. Later that
night, I went down into the fish room. Flashlight in one hand and turkey baster in the
other, ready to do the dirty deed! Now, I was told that keeping an aquarium was supposed
to relieve stress. Nothing but a lie! This was serious business I was very nervous about
what I had to do next in order to get Dicrossus filamentosa fry. The automatic
timer had shut off the lights just minutes before. But having thoroughly planned and
rehearsed what was to happen next, I knew just what to do and where the fry would be. They
were back on the leaf - yes, every night the mother would put them back up there. As I
began to suck them out with the baster some began to fall off the leaf into the darkness!
This was turning into a debacle! My heart was pounding like an air chisel! After what
seemed like hours (10 minutes) I was able to get about half the fry. I decided right then
to leave some, in hopes that the female would not totally freak out.
The fry were nothing more than specks! A mere 2-3mm long. The following morning they
were still alive. The worst was over, or was it? As long as the fry were still with yolk
sac they were not going to feed. Several days later they were just barely free swimming
and began to feed on Liqui-fry, and once totally free swimming they took newly hatched
Artemia larvae. The tank chosen to house the fry was a 2 ½ gallon tank which had been set
two weeks prior to moving the fry. This tank had been filled with water from the parent
tank. It had a mature sponge filter and Java fern and moss. Once the fry began feeding on
the brine shrimp larvae the worst was over. The only worries now were the proper amount of
food and water changes.
As far as the adults are concerned, they didn’t really seem too upset over the
loss of their young. Within a month they began to spawn again. It is certainly possible to
breed these fish on a regular basis if you are good with a baster!
In conclusion Dicrossus filamentosa proved to be a very challenging fish to
breed. To date, it’s the most challenging for me. I can say that it was certainly a
humbling experience. But I was determined to breed this fish.
References
Horst Linke, Dr. Wolfgang. Staeck, American Cichlids I. 1994
Tetra-Press
Salvatore Silvestri – pers. com. 1998
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