Spawning the Banggai Cardinal

Author: Jack Agliata

While the mouthbrooding Banggai cardinals Pterapogon kauderni are easy to spawn by marine fish standards, the author’s work in progress shows that raising the fry is no cakewalk.

Hooked on Tropical Fish

I still can recall my first sight of a tropical fish. The year was late 1946 or early 1947, I was 5 years old, and our kindergarten class was on a field trip to the Museum of Natural History in New York City. In one corner of the museum was a special display of the Egyptian mouthbrooder, with large pictures on the wall, a brief movie, and a small petri dish with live fry. I would have lingered there for hours absorbing it all in if the teacher would have allowed it.

My First Tank

As “luck” would have it, later that year I needed my tonsils removed, so when my parents asked me what I would like (besides ice cream), I asked for a fish tank next to my bed. My parents bought me a 5-gallon aquarium woefully overstocked with six goldfish, one a black moor. Of course, down the road goldfish gave way to tropical fish, starting with one guppy and one zebra danio.

Intro to TFH

Sometime around August 1954 I discovered a wonderful new world: Tropical Fish Hobbyist Magazine. I immediately became a subscriber and have been a subscriber, uninterrupted, ever since. That means over 50 years of TFH magazines are in my bookcase, as I have also acquired all the back issues prior to that date except for three that I still hope to find one day.

How do I know that Sept./Oct. 1954 was my first TFH issue? Well, it has no cover and still shows the water damage when my Mom’s table broke, taking with it my prize guppies and platies and their 20-gallon home. (I think we paid to repaint the ceiling of the neighbor who lived downstairs in our Bronx apartment building.)

Time Passes

Over the intervening years—other than perhaps the year when I first got married—I have had at least one aquarium in our home at all times. I really enjoyed the new African cichlids in the early 1970s and was part of the Rocky Mountain Cichlid Association when I lived in Colorado at that time. I was one of the few members in the Denver area that also kept discus. In the late 70s I added a saltwater aquarium after a vacation in Tahiti.

I remember finally getting two Moorish idols to eat, and they lived for more than three years with a moray eel and trumpet fish for companions. The idols thrived on my Jack Wattley inspired homemade beefheart/spinach diet, which I made for the discus. Of course in those days, a saltwater aquarium meant lots of gravel, an undergravel filter with powerheads, and dead bleached corals for decoration. But it worked, and it was beautiful.

From 5 Gallons to 200 Gallons

Fast-forward several years. Now living in North Carolina, I have five aquariums, including a 200-gallon room divider between my office room and my TV room/fishroom. This 200 is stocked with wild and “man-made” color varieties of discus, altum angels, Crenicara punctulatum, and cardinal and rummynose tetras. Two of the remaining four aquariums house pairs of discus, one a great red melon breeding pair and the other a pair of wild Heckels that I am determined will spawn someday.

Another aquarium houses four zebra plecos Hypancistrus zebra that I see once a day if I am lucky (I also hope to spawn these). The remaining aquarium is one of those “different” acrylics. It consists of two separate sections, each 24H x 21W x 12D, connected by two “swim-through” tubes, each 6 inches long with a diameter of 4 inches. That gives an approximate volume of a little over 26 gallons in each of the two sections.

I bought this tank with the intention of housing a breeding pair of discus in each section; I planned to block the swim-through tubes by a simple screen so the pairs remained separated from each other. Unfortunately, I liked the idea more than the discus did, so I searched for another use for this tank. A reef tank is what I decided on, and the discus went into the big 200.

Reef Tank Setup

I began reading all of the latest information on setting up reef tanks: Michael Paletta’s The New Marine Aquarium (TFH/Microcosm Professional Series, 2001); Jeff Kurtz’s The Simple Guide to Marine Aquariums (T.F.H. Publications, Inc., 2002); John Tullock’s Natural Reef Aquariums (TFH/Microcosm Professional Series, 2001); Nilsen and Fossa’s Reef Secrets (TFH/Microcosm Professional Series, 2002); and some others. Setting up a reef tank is not cheap, and this two-section aquarium made it even more expensive.


I used two heaters, two canister filters (each with the inflow in one section and the outflow in the other section), a protein skimmer in one section, and a powerhead for water circulation in the other.


Live sand, live rock, hermit crabs, and snails of several species began the process in January of 2003.

When it was ready to accept fish, I added a lawnmower blenny Salarias fasciatus, a pink-spotted shrimp goby Cryptocentrus leptocephalus, two yellow tangs Zebrasoma flavescens, a comet Calloplesiops altivelis, a royal gramma Gramma loreto, a flame angel Centropyge loricula, a percula clown Amphiprion percula (for the grandkids), and finally three Banggai cardinals Pterapogon kauderni. Obviously these fish were not all added at once, but rather over the course of 11 months or so.

I also attempted to add a yellow-headed jawfish Opistognathus aurifrons and a mandarin Synchiropus splendidus, but each of these unsuccessfully tried to imitate a mudskipper, and I eventually found them dried up on the floor. Corals of various types were also added at intervals over that year, and it is a pleasure to watch them expand and grow as the reef matures. Though there are two yellow tangs in the aquarium, each has taken control of one section, so fights are limited to the occasional foray of one into the other’s territory looking for food.

Of the three Banggais, one was immediately chased to a corner, and after a few days I never saw it again. The two Banggais that remained were obviously a pair. One was much larger than the other, and they would constantly swim together from one section of the aquarium to the other, through the connecting tubes. I assumed the larger was the male but really did not make any effort to research their habits or spawning requirements. I did know that the Banggai cardinal was a mouthbrooder, but because of their relatively small size and the constant motion of the other inhabitants, I never anticipated a spawning.

A Surprise Spawning

One afternoon in January 2004, while sitting in my fishroom chair reading the local newspaper, I glanced at the reef tank and saw the larger of the two Banggais doing a little shimmy dance next to the smaller one. The dance was much like the discus shimmy dance, but here the dancing partner was side by side with its mate. I watched for a while, but other chores eventually pulled me away for the day. When I finally sat down to watch television later that night, I noticed the smaller of the two had a noticeable mouth bulge, exactly like an African Rift Lake mouthbrooder!

After a few minutes it turned toward the aquarium front, yawned, and briefly exposed a pink/orange mass of eggs in its mouth. Unbelievable!


When I went to bed that night I really had no expectation that the Banggai would still be carrying eggs the next day. But in the morning the little fish still had a big mouthful of eggs. I needed to find out more about the post-spawning procedure and how to handle the fry of these beautiful fish. I found two relatively recent articles in TFH issues (May 1996 and November 2002).

On the Internet I discovered a few additional articles on spawning and the raising of fry. I was surprised to discover that it is the male that carries the eggs in his mouth and the female that performs the little spawning dance. The second dorsal of both fish was equally long, but as I read, the female has a square jaw line, which agreed with my observation for the Banggai that was not carrying eggs in my aquarium.


There was no consensus as to how long it took for the eggs to hatch, but it appeared to be in the range of 18 to 20 days. As for the expelling of the fry by the male, the articles I reviewed indicated a range from day 21 to day 30, perhaps over several nights within that period. Broods are relatively small—less than 30 was probably what I would see (hopefully).


I should indicate here that I did not use any special feeding regimen to get the Banggais to spawn. I fed all the fish freeze-dried and frozen plankton, frozen brine shrimp, and several of the various frozen “formula” foods on the market. Flake foods were also fed twice a day by two automatic feeders, one for each aquarium section.

Tank Parameters

The aquarium parameters at the time of the spawning were: temperature 78°F, pH 8.1, and salinity 1.023—with ammonia, nitrite, and nitrate all negligible. About 18 to 20 gallons of water was changed every two weeks.

Getting Ready for Fry

I decided that if I wanted to see any live fry I had to remove the male Banggai from the reef to a smaller nursery. Four days after the egg-laying I optimistically set up an 8-gallon aquarium with water from the reef tank and a small piece of live rock, and I added a small urchin to “seed” the aquarium and monitor water quality. A sponge was placed over the intake of the overhead filter, and a sponge filter was added also. Several plastic plants were included for the safety of the fry I hoped to see.

Catching the Male

All I needed to do now was catch the male Banggai in the reef tank. Right! I just could not see myself tearing down all that beautiful live rock, even if only for a few minutes. Some of the coral had now grown onto more than one rock piece, so at best it would be a destructive process. I had a wild idea; if I could somehow trap the male Banggai in a minnow type trap, the procedure would be “painless” for the fish and for me.

Minnow traps employ a funnel shape, wherein the fish find it difficult to exit after they swim down the funnel, through the smaller opening, and into a receptacle. I found exactly what I needed in an aquarium supply catalog: a minnow trap top that screwed onto a jar. It was about 4 inches wide with a small fish opening of about ¾ inch.

I knew that the two Banggais primarily used the upper tube to swim from one section to the other. The opening of ¾ inch was too little for any fish to swim through, with the exceptions of the royal gramma, the percula clown, and the Banggais. The percula rarely moved away from his coral home, and the gramma rarely ventured from his rock cave, so I wasn’t worried about them interfering.

I placed the trap in the swim-through tube on day 14 after the eggs were laid, and it took only 1½ days to catch the male Banggai. My guess is that had I placed the trap top in the tank earlier to acclimate the fish to its placement, the capture would have been a bit quicker.

The Fry

On the day following the move of the male to the isolation tank I noticed a round little ball with a big eye staring at me from the tank floor. It was clearly an egg, and it was alive. Since I was going away for four days the next day, I picked up the egg/fry and placed it in a little fry nursery tank within the male’s tank. Looking at it closer, the fry had obviously hatched but had not fully opened. It was almost all egg yolk all curled up.

Finding More Fry

I had no idea what to expect upon my return a few days later. I was surprised to find not only that fry still alive, but also four additional fry in similar condition on the tank floor. This was day 21 after the egg-laying. I removed the newly seen fry with a turkey baster to the little fry tank. If I had to compare them in size, they are bigger than guppy fry at birth for sure—more like the size of Tropheus moorii fry, at perhaps 1/8 of an inch long. On day 22 I found six additional fry on the tank floor. A few were fully extended but still with large egg sacks. So now I had 11 Banggai fry in the nursery.

The male Banggai looked like he might have a few more fry in his mouth, so I did not attempt to feed him or move him. I have no idea why all fry were released prior to the swimming stage. The tank itself was fully covered with a towel so there could not have been anything to frighten him.


On day 23 I found one of the fry dead in the nursery tank, but then I found another live fry in the tank with the male, so I still had 11 live Banggai babies. Since all the fry were now swimming in the nursery I began feeding live baby brine shrimp at this time. I have used brine shrimp kits for discus fry and for African cichlid fry with great success. They are inexpensive, and since I never have too many fry to worry about, two of these kits are more than enough for a constant supply of baby brine.

By starting one culture the day after the first, you never run out of live baby shrimp. I added hatching mix, as the articles I read indicated the fry need added vitamins, unsaturated fatty acids, and other enrichment along with the baby brine shrimp.

It appeared the male might still have a few more babies in his mouth, so I still did not attempt to feed him. I did suction out uneaten food from the fry tank each night using the turkey baster, and I changed a gallon of water every other day out of the male’s compartment, which did not appear to disturb him in the least.

On days 24 and 25, the 11 Banggai fry continued to eat ravenously, while the male still had a big mouthful.

On the morning of day 26 I found another Banggai fry swimming next to the male, who no longer had a bulging mouth. I removed that fry to the nursery tank and fed the male about a half dozen live blackworms that he eagerly consumed. A few hours later I again fed him about the same amount of live worms; it appears he went 26 days without eating anything or even making an attempt to eat. He certainly did not look at the fry as food, no matter if they were on the tank floor or swimming by his side. I returned him to the reef tank on day 29, and he was greeted by the female with a flaring and bulging mouth display. Six days later he was once again carrying a full mouthful of eggs.

The result of this first spawn was 13 live fry, one of which died without ever reaching the free-swimming stage.

Now What Do I Do?

Even though I removed the male to the reef tank, I decided to keep the 12 fry in the smaller nursery tank, floating in the male’s former home. From the few articles that I read, getting the proper quantity of food to the fry seemed like an issue. By keeping the fry in the smaller confined space of the nursery, I hoped to eliminate that problem.

No Aggression

Of course I had to be concerned about aggression among them, but at this stage I had not noticed any attempt by one fry to chase another. The fry were fed at least five times a day with the live enriched baby brine when it was possible. On day 38 I awoke to find one fry dead and two more lying on their sides and breathing rapidly. I immediately performed a 25-percent water change, but the two fry would only swim weakly when I used the turkey baster to generate water movement.

Additional Labor

While I read that trouble was to be expected after the fry had been free-swimming for 10 days, it still caught me by surprise. Other than a significant and rapid change in water quality, which I could not confirm, my guess is that the fry were starving. The prior day I was only able to feed them three times, and nothing after 5 p.m. because I was not home. It appears that Banggai fry need an almost constant supply of live baby brine during daylight hours. In the next two days I lost two more fry, again with the same symptoms of them lying on their side with heavy breathing in the morning. I immediately did a 50-percent water change. Because my wife and I were going to be away for a week I began feeding the fry with a mixture of live baby brine and frozen baby brine soaked in a HUFA supplement.

It appeared the seven remaining fry continued to eat the live baby brine, but whether they consumed any of the frozen brine I could not tell. Apparently they did not because when I returned from my week vacation all the Banggai fry had succumbed. During my absence the pet sitter visited the house once a day to feed the parrots and other fish, and obviously the once-a-day frozen cube of baby brine shrimp was not enough to stimulate their feeding behavior.

Looking Ahead

Based on this one experience, as well as the things I have read, getting your Banggai pair to spawn and seeing the fry is the easy part. The difficulty apparently is in raising those fry to maturity, even though they are rather large at birth. Enriched live baby brine shrimp is apparently part of the answer, though with my limited experience I certainly cannot confirm that this is the only way to go.

Next Feeding Trial

For the next spawn I want to try vinegar eels and microworms in addition to the baby brine shrimp. Another change I want to make in the future is to use the main reef-tank environment and water to raise the fry. Controlling ammonia, nitrates, and nitrite in a recently set-up 8-gallon aquarium is much more difficult, especially with the constant feeding of the fry. My plan is to place a net-type fry hatchery in the main reef tank after the male releases the fry in the 8-gallon isolation tank. If I can place this raising hatchery near a water flow that is not too strong in the reef tank, then I would be assured of constant water parameters for the fry.

Final Thoughts

While I was very disappointed in this first attempt to breed and raise a saltwater fish, I was amazed by the unexpected adventure of it. And hey, I just read that you might be able to house together and breed two comets Calloplesiops altivelis. Maybe I’ll go to my local fish store and pick up another one of those…