In October of 1997, Dr. Wayne Leibel was speaking for the Milwaukee Aquarium Society’s Fall Speaker Workshop, and brought some Aequidens diadema for the rare fish auction that followed. As usual for an event of this type, I had to get something new to the hobby or rare in our area or some fish I have not yet bred. With all that said, I bought a bag of four Aequidens diadema. When I got home, I put the fish in a thirty five gallon tank that was open. The tank was setup for New World cichlids, with an inch and a half of fine gravel and two pieces of driftwood. A water temperature of 80 degrees Fahrenheit, with a pH of seven and soft water, a Whisper two power filter for filtration and a twenty four inch fluorescent standard bulb for lighting. Their diet consisted of cichlid pellets and was supplemented with live adult brine shrimp.
About a year had passed and I was down to three fish. Tom Wojtech, who had received six of Wayne’s diadema, was down to one fish and gave it to me. I quarantined the fish in a twenty gallon high tank. Over the period of a few more months I lost one more of the original diadema.
While at the American Cichlid Association Convention that was hosted by the Great Lakes Cichlid Society of Cleveland, Ohio in July of 2000, I purchased four diadema that were around two inches in length from the Guy Jordan silent auction for $35.00. When I got home I put the fish into a thirty gallon tank, with a similar setup as the first fish. One of the fish was a little larger than the others and was growing at a faster pace. There was some aggression in the tank and with in a month I had a dried up fish on the floor. Over the next couple of months I lost one more due to the bully.
The diadema tally as of August 2001 was two of the original fish, one from Tom and two from the ACA. Time to get serious about getting this fish to spawn. So I decided to do some mixing and matching. Tom’s diadema, a nine inch fish, went into a seventy five gallon tank with an inch and a half of fine gravel, two six inch rocks, two fifteen inch pieces of drift wood and one six inch clay pot. A water temperature of 82 degrees Fahrenheit, a pH of seven and soft water, a Whisper one power filter and one air stone for filtration and a twin four foot shop light with standard fluorescent bulbs for lighting. She got the tank to herself for a week to acclimate and own it. I am assuming that this fish was a “she” due to my observations. I started to feed heavier on live adult brine shrimp. I now moved the larger of my original fish, all of ten inches, to the seventy five gallon tank and the smaller of the ACA fish with the other one of my original fish in its thirty five gallon tank.
There was some activity in the tank that contained Tom’s fish and the large original fish that I assumed to be a male. Being impatient, I removed the large male after two months, since no eggs had been laid to that point. I decided to put the larger of the fish that I also assumed to be a male, from the ACA into the 75. I noticed a lot of flirting and spawning activity during the first week. Within one month eggs were laid on December 12, 2001 between 5:00 a.m. and 8:00 a.m. After they appeared to be done spawning I removed the male because he had become very aggressive. It turned out that Tom’s fish was indeed a female.
Since I was laid off from my job, I had a lot of time on my hands and spent quite a bit of time in the fish room watching the development of the eggs and eventually the fry. The eggs had been laid on the inside of a 6″ clay flowerpot. The eggs were opaque in color, and there appeared to be between 200 and 300 of them. I pulled the pot and put it in a 5 ½ gallon tank seeded with water from the parents’ tank. I put Methyblue into the tank until the water was a deep blue, and the eggs couldn’t be seen. I placed an air stone in front of the pot for water circulation.
The eggs hatched on December 14th, approximately 60 hours from when they were laid. During the preceding time I carefully removed any eggs that turned bright white (this could be easily seen through the dark blue water). At this time I started to do daily 40% water changes, since I was still off work, and I didn’t want to chance losing any of the fry.
On December 16th, I noticed the tiny hatchlings had one spot in the middle of their tails. By December 19th, they also developed a spot in the middle of the body. On December 25th most became free swimming. Only a few were still bouncing off the bottom of the tank with their yolk sacs still attached. I started feeding baby brine shrimp on December 26th. By December 28th I could actually notice a dorsal fin on a few of the fry. There were now only between 60 and 70 that had survived.
By January 4th their heads appeared to be rounded and the eyes were forward. Their mouths appeared to be turned down. I could also distinguish an anal fin at this time. Around the 10th of January the two spots began to fade. By the 16th of January, the fish started getting vertical black bands on the dorsal fin and back half of the body. I introduced flake food into their diet at this point. They ate it without any hesitation. I continued to feed baby brine after the flake food was gone. A black spot appeared in the middle of the body around January 26th. By the next day they were large enough to eat adult baby brine.
I tried to reintroduce the male and the female at this point, but since she had owned the tank by herself for so long, she became the aggressor and chased the male right out of the tank. He fell a good six feet to the floor, and even though I scooped him up soon after he hit the floor and placed him in his tank, he must have had severe internal injuries and lingered a few days before dying.
I was so relieved to be able to turn in six of the fry for my BAP points at the MAS general meeting on February 22nd. It only took over four years plus a lot of patience, to be the first in our club to have a successful spawn of Aequidens Diadema.
Author: Ray Gettler; Splash, Milwaukee Aquarium Society
Source: Aquarticles (no longer available)
Copyright image: F. Ingemann Hansen – Akvariefotografen.com
