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Re: "Jay DeLong" <jdelong at nwifc_wa.gov>: NANFA-- annual meeting update
SUCCESSFULLY SPAWNING AND RAISING
THE BANDED SUNFISH (Enneacanthus obesus)
By Peter R. Rollo
2308 Cedar Lane
Secane Pa,
19018
1-610-543-1660
North American Native Fishes Association
In their native habitat in South Central New Jersey, spawning
generally begins in May or when the water temperature approaches
70 F. On July 21, 1994 ten adult Banded Sunfish were collected
from the same body of water as the Blackbanded Sunfish I
collected. The water conditions found at this time of collection
were no measurable hardness, pH of 6.0 and a temperature of 75 F.
>From the literature the spawning process proceeds in typical
sunfish fashion. The males construct a nest in the substrate and
await a ripe female. With the approach of a female, the male
begins to display with fins fully extended. The pair circle each
other and after a short time the pair stops circling, the female
releases her eggs and the male simultaneously fertilizes them.
The males then remain on their nests to fan and guard the eggs.
The adult Banded Sunfish are housed in a 20 gallon high aquarium
and spent their summer in my shed. It is equipped with a
thermostatically controlled exhaust fan to prevent heat buildups.
Filtration is provided by an internal power head attached to a
sponge filter and an air driven corner box filter. Lighting is
provided by a florescent tube situated on top of the tank. By
pushing the light to the back of the tank the light intensity can
be lowered to appropriate levels. An inch and a half of gravel
is provided along with a flower pot turned on its side. There
are no plants in this tank. To aid in the wintering process and
to insulate it from the summer heat the tank is enclosed in a
plywood box with a removable lid insulated with styrofoam. An air
space of about 4 inches surrounds the sides and top of the tank.
In the winter minimal heating is provided using a voltage
regulator connected to heat tape. The heat given off by the heat
tape warms the air space. This warm air is pumped into the tank
by the air pump and effectively prevents freezing or major drops
in temperature. The heat is manually controlled and used only
when excessively cold.
Initially I tried to acclimate the Banded Sunfish to my tap
water, which is hard and has a pH of about 6.8. They started off
doing well but within two weeks their health started to decline.
Their appetites decreased and the most noticeable change was that
they lost most of their color. Since it was clear they would not
thrive on my terms I went to work turning their tank water into a
close duplicate of their natural habitat. The first problem to
solve was how to soften the water with the least effort. I
decided to use a rechargeable ion exchange softening pillow,
which is placed in the filter box. Using a five gallon container
and an extra power filter, I softened the water to levels that
could not be measured by my test kit. I also added Blackwater
Extract to the softened water. The softening process takes about
one and a half to two hours per five gallons. Prepared water is
stored in five gallon bottled water containers with lids. When I
had prepared enough water, I changed the water and observed any
changes. Within 48 hours the fishes natural color returned and
they became active and hungry again. Softening the water appears
to be a very important factor for maintenance of healthy fish.
The next problem was how to acidify the water. While softening
the water, I added pH Down to the water till I reached a pH of
6.0 to 6.2. The fish were slowly acclimated to this new water.
Once completely acclimated I sampled the tank water pH and found
it to be 6.8 instead of 6.0. I had neglected to consider that my
tap water has a high buffering capacity and the pH will rebound
to higher levels unless you exhaust the buffering capacity of the
water. The next time I made water and adjusted the pH to 6.0 I
waited several hours and checked the pH again. It had rebounded
as it had in the tank. The pH was adjusted again and let to sit
overnight. This time the pH remained the same. As an aid to the
acidification and conditioning process, I also filter the water
through peat for 24 hours prior to storage or use. The completed
water is tea colored, as it is in their native habitat, and takes
a day to make five gallons of water, but with the results I have
gotten it is worth the trouble.
In the summer the sunfish are fed moderately every other day, and
in the winter they are fed sparingly every three or four days
whenever the water temperature rises above 50 F. Below 50 F the
food in their stomachs digests so slowly that it can actually
spoil before digestion is complete, killing the fish. Besides, I
am trying to recreate their natural environment, and minimal
feedings in the winter is part of it. The foods offered in the
summer include frozen and freeze dried bloodworms, frozen
glassworms, small live crickets, small live cut up garden worms,
live daphnia, frozen shrimp, live mosquito larva, live black
worms and any other small insect I can catch. The winter diet for
these fish will be the same as that in the summer except for some
of the live foods that cannot be cultured indoors, caught or
bought.
As with my experiences with breeding Green Sunfish, the fish
endured an average summer temperature of about 80 F and will
experience average winter temperatures of about 40 F. Thirty-
three percent water changes are made once a week spring, summer
and fall. Twenty-five percent water changes are made about once
a month in the winter (when water temperatures are consistently
below 55 F). Don't be lax with water changes. These fish may be
small but they have big appetites and produce large amounts of
waste. It is extremely important that all water added to the
aquarium during water changes be the same temperature, pH and
hardness as the water in the aquarium or you run the risk of
stressing or killing the fish.
It is now early November and all is going well. I noticed that
some of the Banded Sunfish appeared heavier than normal, but
thought it a result of regular feedings. Several days later on
November 6, 1994 at about 10 AM I noticed that one fish, with
colors more intense than normal, was hovering over a small
depression in the gravel, but not allowing any other fish near
it. Upon closer examination I noticed another fish in the act of
spawning with the hovering fish. I was not lucky enough to
witness the entire spawning sequence but I imagine their spawning
ritual is similar to that of the Blackbanded Sunfish. Apparently
the dominate male had spawned with all ripe females and was
guarding the eggs. All fish that appeared heavy the day before
were now thin. The fertilized eggs are adhesive, perfectly
round, colorless and between 1/32 and 1/16 of an inch in
diameter. The male constructed a shallow circular nest typical
of sunfish.
I quickly removed all the fish and put them in a reserve tank I
had set up in the house. The spawning females were a bit ragged
with torn fins but otherwise in good shape. The power sponge
filter and corner box filter were removed and replaced with an
air driven sponge filter to ensure that none of the eggs or fry
would be sucked into the filters. Air flow was high enough to
cause a light current in the aquarium. The current prevents any
harmful material from settling on the eggs and wigglers. A 25%
water change was also made.
I now anxiously waited for the eggs to hatch. No chemicals were
added for egg protection. Clean, well filtered and aerated water
is sufficient. Based on my reference books the eggs of this type
of sunfish hatch in 3-5 days depending on temperature. On
November 9, 1994 the Banded Sunfish eggs finally hatched. It
only took 3 days at a water temperature of 65 F and a pH of 6.0.
There were no apparent problems with bacterial or fungal
infestations of the eggs as evidenced by the number of eggs that
hatched. The wigglers were entirely clear, no visible markings
could be seen. Within 24 hours eye spots became apparent and the
wigglers started to take the form of fish 24 hours after that.
Twenty-five percent water changes are made every week and so far
all is well.
With regard to how long it takes for the wigglers to become free
swimming, my references estimate a few days to about one week
depending on water temperature. On November 12 I noticed a few
fry making their first attempts at swimming on their own. By
November 14, five days after hatching, all wigglers were free
swimming. I offered a very small quantity of brine shrimp but
none were taken. Two days after all fry were free swimming brine
shrimp were again offered and accepted. Generally, one to two
days after the fish are free swimming they will accept newly
hatched brine shrimp. Feedings began twice a day, once in the
morning and once in the evening. The feedings require that the
aeration and filtration be turned down to a minimum or turned
off. This prevents the shrimp from being sucked into the
filtration system and aids the somewhat uncoordinated fry in
catching their food. The young fry cannot successfully capture
the moving shrimp in moving water. With still water it takes
them several attempts before they can capture the shrimp. This
will quickly pass as the fish grow and become proficient
swimmers. It is easy to determine which fry are feeding. Since
their bodies are still transparent, consumed shrimp give the fry
orange bellies. For variety the fry are also given
microworms. I estimate that I have about 50 Banded Sunfish fry.
Once the adult fish are transferred to their winter quarters any
chance of additional spawnings will be eliminated as the water
temperature drops. This will be a welcome relief because all my
available tank space is devoted to the rearing of the Banded
Sunfish fry and the Blackbanded Sunfish fry at various stages of
development.
Several months have passed and the fry are about a 1/2 inch in
length. The fry are still dependent on brine shrimp and
microworms. Attempts will be made to wean these fish off the
live foods as soon as they are large enough. I was successful in
doing this with the Green Sunfish and hope I will be able to
succeed with these fish.
As they have aged, the young sunfish are beginning to show
physical attributes of adult fish. The Banded Sunfish have clear
fins and a golden straw body color. No other coloration is
visible as yet, but are expected to color up more as they age.
>From my experiences with breeding Green Sunfish, cannibalism of
the smaller fry by the larger fry began at about this time. So
far the larger fry have not attacked the smaller fry, as did the
Green Sunfish. My feeling is that their mouths are too small to
cause any damage at this age, let alone swallow their smaller
tankmates. The Green Sunfish were much more aggressive and
equipped with large mouths capable of easily swallowing their
smaller tankmates.
This group of fish will be overwintered as naturally as possible
in my shed as described earlier, and I look forward to spring
when I hope to experience additional spawnings of the Banded
Sunfish.
REFERENCES
1. Thompson, Peter. 1985. Thompson's Guide to Freshwater
Fishes. Houghton Mifflin Company. 205 pp.
2. Quinn, John R. 1990. Our Native Fishes. The Aquarium
Hobbyist's Guide to Observing, Collecting and Keeping Them.
Countryman Press. 242 pp.
3. Raasch, Maynard S. & Altemus, Vaughn L. 1991. Delaware's
Freshwater and Brackish Water Fishes. A Popular Account.
Claude E. Phillips Herbarium. Delaware State College. Dover,
DE. and Society of Natural History of Delaware. 166 pp.
References: