SUCCESSFULLY SPAWNING AND RAISING THE BANDED SUNFISH (Enneacanthus obesus)

      By Peter R. Rollo
      reprinted from American Currents, Fall 1994

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.

banded sunfish Enneacanthus obesus (© Atlas of North American Freshwater Fishes)

Used with permission. Article copyright retained by author.

© 2005 North American Native Fishes Association