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45 Years of Hi Fin Swordtail History and Breeding

Original article can be found here  From Select Aquatics 


In 1965, I visited a small tropical fish store on the east side of Houston, Texas -- Graham's Guppy Harbor. Mr. Graham had converted the large garage behind his house into a small tropical fish store. By the name, it is easy to guess that Mr. Graham specialized in guppies. He was one of the first serious breeders, on a large scale, of show quality veil and delta tail guppies in Houston. Mr. Graham had placed an ad in the local newspaper selling his guppies and I asked my father to take me to buy a pair of Mr. Graham's green delta tail guppies. While looking over all the aquariums full of fish I stopped before a tank of swordtails the likes of which I had never seen. These brick red swordtails did not have the usual dorsal fins, but rather huge sails flowing down their backs. The label on the tank read: Simpson Hi Fin Red Swordtails $6.98 a pair. I was transfixed before this tank. These fish were gorgeous. I wanted a pair and I offered to skip the guppies, but the price tag was just too big and I had to leave empty handed. Mr. Graham tried to ease my disappointment by telling me that the fish in the tank were the leftovers of the shipment and that I should come back when the next group arrived. He said that there were always a few males in each shipment that would just knock my socks off. I took my guppies and left, knowing I would be back. Little did I know that Simpson Hi Fin Swordtails would be a part of my life, off and on, for the next 45 years.    Image of Simpson Swordtail




This new strain of swordtails was formally introduced to the national aquarium hobby in late 1960 and early 1961 through the pages of the period's three big tropical fish magazines: The Aquarium magazine, the Aquarium Journal and Tropical Fish Hobbyist. (At the time, TFH ran two features within a few months of one another on the development of this fish.) I believe the article and accompanying photographs, both by the late great aquarist Gene Wolfsheimer, which appeared in the November 1960 issue of the Aquarium Journal, was the first report on this fish to reach a national audience. (Wolfsheimer is all but forgotten today, but he was one of the finest aquarists in the history of our hobby, a legendary breeder much like his old friend Rosario LaCorte.) Calling these new fish "The Simpson Swordtail," Wolfsheimer wrote in the Aquarium Journal that, "Mr. and Mrs. Thomas Simpson of Gardena, California, [a suburb of Los Angeles] happened to see the first little high-finned swordtail, Xiphophorus helleri, swimming about with its normal brothers and sisters. It was saved because it was ‘so cute.’ This fish turned out to be a male. The original parents are somewhat obscure but one was a brick red male and the other a ‘blue’ swordtail." The little high-finned male turned out to be brick red and, according to Wolfsheimer, "as his mates he was given a number of velvet red swordtail females."

The first pairing of high-finned male to low-finned female was a success. Many, but not all, of the offspring of both sexes sported the large dorsal fin. The gene for this new mutation had turned out to be a dominant one. Not surprisingly, the range of color types found in these early batches of babies was rather wide. Wolfsheimer noted that "one spawn can include various shades of red as well as golden and some green." He also suggested that a breeding program using red velvet swords alone will, in time, produce "a true strain of this long-finned red swordtail."

Three months later, in the February15 - March 15, 1961 issue of The Aquarium magazine, Wolfsheimer once again reported on what he was now calling the "Simpson High Fin Swordtails." While the Aquarium Journal had placed one of Wolfsheimer's color photographs of a pair of these new fish on its cover, The Aquarium magazine simply ran a nice black and white Wolfsheimer photograph of the same pair of fish with its article. The "news" regarding these swords in The Aquarium magazine feature was a small ad placed by the Simpsons themselves in this issue. It announced the availability of their new "Hi - Fin" Swordtails. The fish were advertised as "The SWORD with the New Look!"  Now anyone could purchase the Hi-Fin Swordtail from the Simpson's hatchery in California. (I believe Joanne Norton was one of the Simpsons' early customers.) These small ads ran for the next several months in The Aquarium magazine and constitute the first national distribution of this fish. In time, the Simpson’s would open a tropical fish store themselves. Florida fish farms would soon begin breeding the strain, although never with great success. (The fancy sword program in Florida farms caught fire a few years later (1966) with the arrival of a more commercial, prolific, larger and easily handled Xiphophorus mutation – the Lyretail Swordtail.)

TFH first reported on this new variety of livebearer in an article by Thelma Simpson herself in the March 1961 issue. The piece was entitled "How I Developed the Simpson Swordtail" (The name "Simpson Sword" would slowly, over the years, give way to the more literally descriptive "Hi - Fin Swordtail"). In her article, Mrs. Simpson outlined how she became interested in goldfish as a child in Kansas and how she began raising tropical fish when she moved to California. She goes on to cover how she found the lone "hi-fin" male and proceeded to breed him. He lived a long time as Mrs. Simpson was able to breed this original male to his great-granddaughters! The strain, according to Mrs. Simpson, produced both small, early-developing males and large, late-developing males. Some of her fish reached 4 inches in length.

The second TFH feature was a personality piece on Thelma Simpson. (Mrs. Simpson was the "senior" partner of this "fishy" team.) It appeared in the November 1961 issue of TFH. There was a black and white photograph of Mrs. Simpson working in her hatchery and the author, William Vorderwinkler, described the beginnings and recent evolution of the Simpsons' backyard tropical fish hatchery. The hatchery was set up in the late 1950's in a converted double garage to raise swordtails, platies, Corydoras catfish and bettas, with bettas being the main focus until the Hi - Fin Swords came along.

It is interesting to note that Thelma Simpson was a member of a remarkable group of aquarists in the Los Angeles area at that time. They had all grown up around the now defunct Los Angeles Aquarium Society, which was started in the late 1940's by Wolfsheimer, Dick Haas and others. LAAS was extremely active in the 1950's and 1960's, hosting large annual shows, one of the first AKA conventions (1964) and several members were regular contributors to the Aquarium Journal. In addition, under Wolfsheimer's editorial leadership, LAAS supplied a large percentage of the authors for that remarkable series of popular aquarium books put out by the Pet Library in the late 1960's. It appears that several members of LAAS joined the Simpsons in raising and distributing the Hi - Fin Swordtails. Now that is an active society!

The various articles mentioned above might be said to chronicle the first phase in the history of Hi -Fin Swordtails in the aquarium hobby. The next phase would see the development in 1963 of the first Hi - Fin or "Topsail" Variatus Platies by Bill Hearin at his Florida fish farm using the Simpsons' fish and low fin variatus type platies as breeders. Shortly thereafter, Dr. Norton would introduce Hi - Fin Maculatus Platies. The next exciting fancy swordtail introduction would be the before mentioned Lyretail Swordtail. It was developed at the Florida fish farm of Oren and Don Adams, probably between 1963-1965, and introduced in 1966.  Before too long, the hi - fin and lyretail genes were combined to create the stunning Hi - Fin Lyretail Swordtail. (Although, at the time, the slight enlargement of the dorsal fin caused by the gene for lyretail in a low-finned swordtail led some to mistake simple lyretailed fish for true Hi - Fin Lyretail Swordtails. This mistake is still common today despite countless articles over the years explicitly pointing it out. It makes one wonder about the eyesight of some aquarists!) Before too long, (late 1960’s) a devoted group of Hawaiian hobbyists, led by Glenn Takeshita, succeeded in developing lyretailed variatus and maculatus platies. The Europeans were also fascinated by these new fancy finned swordtails and hobby articles, photographs and genetic research covering these fine fish began to appear there -- particularly in Germany.

Once these various "fin" strains were established in the hobby, the push for new colors took off, rivaling the breeding experiments using swords and platies that occurred in the hobby in the 1930's. Hardly a month passed without TFH or The Aquarium magazine running an article by Norton, Takeshita, the sadly forgotten Steve Saunders - originator of the gorgeous but now lost Widetail Veiltail Molly strain - and others describing some new color cross or mutation. Most of these strains were short lived, but their existence created quite a "buzz" in the hobby.

Books soon followed. The Pet Library published: Enjoy Your Platys And Swordtails by Klaus Kallman (Myron Gordon's student), Know How To Breed Livebearers by Al Klee ( A color photo by Wolfsheimer of the same pair of beautiful brick red Hi - Fin Swords that he used in the photos found in his previously noted articles in the Aquarium Journal and the Aquarium Magazine appears on page 29 of this book.), Enjoy Breeding Livebearers by Dick Haas and the classic Enjoy Your Modern Swordtails And Platys by Dr. Joanne Norton. In addition to these books, two important reports on raising fancy swordtails appeared in two of the hobbyist magazines in the late 1960’s and early 1970’s.

In its summer 1971 issue, the short lived Tropical Fish World magazine ran an amazing article on the swordtails of John and Hedy Kirschmann. The Kirschmanns' New Jersey basement fishroom contained 120 plant filled tanks primarily devoted to fancy helleri types. They raised show quality specimens (huge) outside in a 2000 gallon, 8 feet deep pond and inside in several specially constructed extremely large aquariums. Two walls of the Kirschmann fishroom had been knocked out and replaced with glass bricks to allow the sun to develop the rich colors in fish that only sunlight can achieve. (LaCorte and Wolfsheimer both went out of their way, by using skylights, to get sunlight into their fishrooms too.) The article in Tropical Fish World magazine spotlighted the "Dovetail Swordtail" the Kirschmanns had developed by crossing Black Hi - Fin Lyretails with their strain of large Red Hi - Fin Swordtails. The "dovetail" was simply the "comet" platy caudal fin pattern transferred to swordtails. The Kirschmanns freely shared their methods of breeding and raising superior fish in the article.

As impressive as the Kirschmann piece was, it could not compare to a method presented two years before in an article in The Aquarium magazine of June, 1969. This article both outlined a sure fire method of raising top quality helleri with just a few home aquariums and provided proof of its approach with stunning photographs of enormous, highly colorful and basically perfect Hi - Fin Lyretail Black Swordtails. The article was by Lloyd E. Groenke, an Atlanta Lutheran minister at the time, and was entitled "The Super Sword".

Groenke's method of producing fine fish was so exacting that I will both quote and summarize his suggestions. He started with culling. Groenke wrote, "Heavy culling is absolutely necessary.” He gives an example of what he means, “Within a 24 - hour period, three of my best females had young. There were 103 total. Thirty were culled out at once because they lacked the proper body color. During the next seven days, five more were culled out because they did not develop properly. At three weeks I culled out all the low fins. This left 48 hi - fins, Simpson and lyretail. Of these 48, about 10% to 15% will qualify as first class breeders."

Next, Groenke dealt with environment. He told of how he tried to duplicate the swordtail's natural environment. Groenke noted, "The swordtail, in its natural habitat, enjoys fresh clear running water. I use airstones very extensively. This increases the oxygen supply in the water and forces the fish to swim. The more they exercise, the more they eat; consequently, they grow faster. Airstones also help to expel gases. During the first four weeks of the fry's life, I use two or three airstones per 10 - gallon tank."

Groenke goes on to say that he used a power filter and a sponge filter on each tank and, during the first four weeks, changed one tenth of the water every other day on the fry. After a month, Groenke decreased the airstones, fed less and water changes became one tenth once a week. He commented that the first 4 weeks were the crucial time of development in raising fine fancy swordtails.

Groenke's feeding program could break the resolve of the most dedicated breeder. Groenke writes that, "The first week, the young fry continually have live baby brine shrimp from morning until evening. This means about three feedings a day as the brine shrimp live about four or five hours in the aquarium water. By the second week they have grown considerably and should be fed brine shrimp, live or frozen, every two hours or about eight times a day. At three weeks, I start adding some dry food."

At four weeks of age, the fry were still in the 10 gallon tanks in which they were born and, according to Groenke, it was now time to move them. He used 15 to 30 gallon tanks depending on the number of fry involved. His feeding program also changed. Groenke reported that he now employed a greater variety of dry food, along with tubifex worms, adult frozen brine shrimp, live baby brine shrimp and his own paste food. This menu was offered for the next four weeks and the fish were fed about six times a day. At the age of two months, Groenke wrote that his fish had achieved a two inch body size -- three inches if the tail was included. At this time, Groenke culled or sold everything but his future breeders.

Groenke gave these future breeders about three gallons of water per fish in a 30 - gallon aquarium. He also decreased the feeding schedule to three times a day. This decrease was based on Groenke's belief that it gave "the reproductive organs a better chance to develop." He wrote that he had "noted from past experience that some females which were force fed would not reproduce” and when he cut down on feeding, "within a few months they began to bear young." Groenke theorized that, "With constant forced feeding, much of the oxygen that is taken in by the fish is used to aid organs of digestion, and the result is that the reproductive organs get less oxygen and do not always develop properly."

Whenever anyone asks me for advice on raising fancy swordtails, I always give them a copy of Groenke's article. Few people can meet its ideal procedure, but it sure does set the bar at the level of a real challenge. The only place where I differ from Groenke is on water changes. I agree on the number of water changes for the young fry but I change a larger percentage – say 50-80%. On the sub-adults and adults, I also change a larger percentage of water than he did (80%) and change it more often (2-3 times a week). Of course, this assumes one has a good source of properly aged and treated water at the right temperature ready to go. Individual localities, fishrooms, schedules and/or water problems need to be considered when following this plan. The water must be chemically right and acceptable to the fish. What works for one person may not work for another. Proceed with caution.

The third phase in the history of Hi - Fin Swordtails in the tropical fish hobby was initiated by Dr. Norton with her call for the development of strains of Hi - Fin and Hi - Fin Lyretail Swords carrying long, wide dorsal fins in both sexes. With the introduction of Hearin's magnificent “Topsail” or Hi - Fin Variatus Platies in 1963, it quickly became apparent that the hi - fin helleri strains were producing a number of small bodied fish -- particularly males -- that possessed rather narrow, short and often deformed dorsal fins. (Wolfsheimer first noted the appearance of small bodied (early developing) hi - fin males in the Simpson strain in his Aquarium Journal feature.) People began to wonder how the helleri strains of hi - fins might be bred to carry the extraordinarily uniform, large and very full hi - fins of the variatus males in Hearin's strain.      

I believe Dr. Norton first brought this dream of long, wide hi - fins on large bodied helleri-based strains of swordtails to the attention of the national hobby in an article she wrote in the December 1970 issue of The Aquarium magazine. The feature was entitled: "Hi - Fin Swordtail Improvement." In this article, Dr. Norton noted that "in some cases it may be difficult or even impossible to greatly improve a strain of hi - hins by selection within that strain. For example, there are some strains in which every hi - fin has a small or poorly-shaped dorsal. This is due to the fact that certain hi - fins have undesirable genetic modifiers of the gene for hi - fin. We need to find and fix strains of swordtails in which there are genetic factors that make the hi - fin dorsal large and wide." Dr. Norton went on to suggest that "swordtails having all or mainly Xiphophorus helleri (swordtail) and X. maculatus (platy) ancestry perhaps do not have the genes that can make the hi - fin dorsal very large. It appears, from observing the progeny of various crosses of hi - fins, that “variatus type” platies are more likely to carry the desired hi - fin modifiers than are “maculatus type" platies." At the end of her article, Dr. Norton wrote that "now I have a promising platy-swordtail hybrid that is fertile and in which some of the males have large body size along with large, full dorsals. While the males have very short swords, some of their sons have longer swords. It is hoped that a fixed strain of hi - fins with this type of wide, full dorsal can be developed from these fish."     

 It would appear that Dr. Norton reached a dead end with her promising platy-swordtail hybrid because almost four years later she was still seeking her ideal of a helleri-type sword with a long, wide hi-fin. In the May 1974 issue of the American Livebearer Association's bulletin Livebearers, Dr. Norton published a special announcement concerning the availability within the ALA of high quality Hi - Fin Swordtail stock. She stated that she had become aware of the demand for high quality strains of Hi - Fin Swords among the ALA membership and had realized that few if any were available. To counteract this, Dr. Norton had acquired several commercially raised large red velvet and marigold female swords and had crossed these with a good strain of large bodied, large dorsaled Hi - Fin Swords bred by ALA member Ike Hancock. Dr. Norton reported that the pairs of fish she was offering for sale to the membership from the initial crosses all contained small bodied males but that the cross, having been based on a large bodied strain, should produce large bodied males in the next generation. Accompanying Dr. Norton's announcement was a black and white photograph of a rather small Hi - Fin Swordtail male sporting a very nice, wide dorsal fin.   

 Dr. Norton addressed the issue of Hi - Fin Swordtails with large, wide dorsals in her classic book Enjoy Your Modern Swordtails And Platys. (This book was published by the Pet Library. Unfortunately, this company had a rather erratic policy regarding the inclusion of publication dates in their books, so I am not sure when Dr. Norton's book first appeared. It might have pre-dated her Aquarium magazine piece, but I doubt it.) She explains the genetics behind the development of large, wide dorsal fins in Hi - Fin Swordtails and calls for the establishment of such strains as the standard in the hobby.   

Based on my experience with raising hi - fin helleri type swordtails, I would like to add something to Dr. Norton's remarks. I do believe, as Dr. Norton did, that the development of high quality large, full dorsals in both sexes of helleri-based strains of hi - fin swordtails (far too often, people ignore the quality of the female hi-fin not to mention the overall need for big-bodied, late developing strains of these fish) is primarily the result of the presence of certain genetic modifiers that create a branching of the dorsal fin's rays and, consequently, large, full hi – fins. I know this as I have produced such fish in my tanks from strains created and maintained over a number of generations. That said, in my experience, over several decades, the percentage of actual high quality helleri type hi-fins compared to run-of-the-mill hi-fins in each batch of fry in any given strain is at best 10-15 % - but the individual fish in that small percentage are truly a sight to behold!)

Putting the all important issue of genetic modifiers aside for a moment, I also believe the enormous difficulty hobbyists have in creating such fish is due not only to the absence of genetic modifiers but involves another more fundamental genetic fact. When comparing the poor quality of most helleri and maculatus type hi - fin dorsals to the often (at least in years past!) almost uniform excellent quality of hi - fin dorsals in variatus platies, no one has ever addressed the genetic based difference between the natural dorsal fin shape of helleri swordtails and maculatus platies and the dorsal fin shape of variatus platies.

X. helleri and X. maculatus have rectangular, rather flat dorsals (helleri) and small, rather high square-like dorsals (maculatus); whereas, X. variatus has a broad-based, rounded and full dorsal fin. I must admit that I too ignored this rather obvious difference for years. It was not until I started breeding Xiphophorus nezahualcoyotl ("nezzies") that I started paying attention to the fundamental difference in dorsal fin shape between the "Big Three" Xiphophorus species.  It even occurred to me that variatus platies and "nezzie" swordtails might be closely related as their body and dorsal fin shapes are so similar. In fact, it was the round, full dorsal fin of the "nezzie" sword that first attracted me to the species.

It is my opinion that the natural shape of the variatus dorsal -- broad-based, round and full -- is partially responsible for the often high quality expression of the hi - fin gene in that species. It would seem to me that the more rectangular, flat shape of the dorsal fin in helleri type swords and the small, high square-like shape of the dorsal in maculatus type platy strains are partially responsible for the inherent difficulty in producing hi -fin strains of these fish that rival the expression of the hi - fin gene in variatus type strains.

No doubt, gene modifiers play a significant role in the development of quality hi-fins. Dr. Norton published photographs over the years of various male and female helleri type swords - and even a few photos of maculatus type hi fin platies - that prove just how large and wide the hi - fin dorsal can be in these fish when the right gene modifiers happen to be present. I have seen such fish in my tanks (helleri) and in photos from the tanks of other breeders (see Dr. Roy Levine’s site and Karl Trochu’s site ). The recent (2007?) arrival of the Chinese bred Red-Eyed Red Hi – Fin Swordtails vividly demonstrates the very real potential for creating extraordinary hi fins on helleri type strains. These new fish are so fantastic that people have even tried to give them a new name, borrowed from the molly – Sailfin Swordtails!

But I also believe the genetics behind the original shape of the natural dorsal fin in each of the three standard Xiphophorus species – helleri, maculatus and variatus - plays a role in the potential development of quality hi - finned fish and that this factor has not received sufficient attention. Possibly, due to certain gene modifiers found in the species, the natural dorsal fin of the variatus platy is more prone to having a branching structure to its fin rays that perfects the expression of the hi - fin gene and this alone accounts for the often excellent quality of the hi fin in these fish. I do not know. But I would imagine the genetics behind the natural shape of its regular dorsal fin play some role in the superior expression of the hi – fin gene in this species. All I know is how difficult it is to produce large, full dorsals in hi - fin helleri type swords – not to mention maculatus type platies. Maybe we should cross the helleri strains with birchmanni, nezahualcoyotl or montezumae. Imagine the potential hi - fin swordtail that could be developed by crossing helleri-based strains with X. birchmanni, X. nezahualcoyotl and/or X. montezumae -- WOW! That said we no longer need to imagine such fish. Just take a look at  Dr. Levine’s webpage.

disappointment by telling me that the fish in the tank were the leftovers of the shipment and that I should come back when the next group arrived. He said that there were always a few males in each shipment that would just knock my socks off. I took my guppies and left, knowing I would be back. Little did I know that Simpson Hi Fin Swordtails would be a part of my life, off and on, for the next 45 years.

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