Legal disclaimer part .... This article should be considered advisory in nature. Always feel free, and indeed you are actively encouraged to consult with a local store. Google similar articles elsewhere on the Internet, and MOST IMPORTANTLY your local aquarium club and society. The conditions spelled out here are optimum, not required.

Our club has the most remarkable father son team, rearing great swords all in one 29 gallon aquarium, where survival of the fittest is the rule. This results in fewer fish reaching adulthood as well as  more females  to males, but the survivors are spectacular, and I have been proud to add their fish to my select breeding stock. Great work Tom and Nick!!

So there are.many different ways to go, this is merely how I do what I do, no more or less. Having kept tropical fish for longer then I care to admit, with ponds and aquariums of all sizes around my house and yard swordtails remain among my favorite, if not my all time favorite. Colorful, hardy, able to get along with MOST similar sized community fish, these perennial favorites in the hobby are also a lot of fun to breed and raise. These great and inexpensive fish come in a variety of colors, with females being slighter larger, at three to four inches. The males are easily identified by the long sword like extension of their lower tails. from which  the species derives its common  name. One final point on breeding stock, try to add fresh blood occasionally. I don't. care how incredible your breeding stock is, over time inbreeding results in less healthy offspring. Google the Hapsburg monarchy, seriously.

Start with good stock. In my current base of San Diego, Pet Kingdom, Octopus's Garden, Vet Pets, and Aquatic Warehouse are all excellent starting points for such stock. While some stores will recommend tanks as small as ten gallons, bear in mind that male swordtails can get frisky, so aquariums ranging in size from 20, 29, 30, or even fifty gallon or larger still are more beneficial not only for breeding but over all fish health. Hiding spots for harassed females such as plants, small cave. etc are recommended, as well as a MINIMUM female to male ratio of at least 2 to one. Water changes matter! Both for breeding and overall health. I do 50% weekly, with fry averaging 20- 50% every 2-4 days depending on the number and size of fry and tank size. I like a temp of 76-78 degrees. Warmer can shorter lifespan, and lower, your fish can sometimes be a bit lazy or languid, and breeding frequency will be affected. Be careful when doing such changes that you attempt to maintain the water temp within a 2-4 degree variation, no more if at all possible.

Always use a good declor agent, there are several out there, Prime is my personal favorite, using double the recommended dose . I drain/vacuum.my tank from the bottom, to remove as much uneaten food and debris as possible into a sink or bucket, using airline tubing . Any fry caught in the tubing end up in the bucket or sink, where they are easily caught in a net and dumped right back in the tank. NO GRAVEL IN REARING TANKS, unneeded and a good place for bacteria and other problems. Generally speaking, females will have a so called Gravid Spot; in lower center of her body, which gets darker as the birthing approaches. Some variations like my fire engine red albinos, are colored in such a manner that this is not a reliable indicator. In these cases, watch as her belly grows, if it starts to get a bit square in the frontal region of her under belly, then you most likely have a winner. I have been faked out, finding a poop laden tank, and no fry so feed a bit less if this occurs with some sort of frequency.

When I started raising swords, the conventional wisdom was breeding traps. Full disclosure, at that point in my life, I also believed in Santa Claus . PLEASE DO NOT USE THESE! Placing a 2-4 inch fish, in a 4-6 inch container, cut in half to allow separation of fry from baby eating mom, ditto dad and most tank .mates,creates .real stress. I have seen great fish become humpbacked.from the stress, especially if you guess wrong as to the delivery date, and mom ends up trapped in the breeding trap for a week or more awaiting delivery. Would you.have wanted your mom to birth you anywhere with the word "Trap" in the title?

If at all possible a delivery tank of 5.5 to ten gallons, 15 gallons at most, bare bottomed, no gravel, but potted and or floating plants, makes mom feel more secure, allows for better, easier tank cleaning, and gives the kids a place to avoid being breakfast, as swords usually birth live babies or fry, in hours of darkness . Sponge filters, which are cheap and baby proof, provide the best filtration for both delivery and fry rearing tanks, until your fry are at least 1/2 to 3/4's of an inch in size. Remember swordtails are notorious jumpers, tight fitting full covers are ALWAYS recommended. Due to the expected delivery  time of overnight, I  like to throw in a super small of amount of freeze  dried bloodworms right before lights out, just to take the edge off moms appetite.

Ideally, it is helpful to have a recovery tank of similar size for mom to spend 1-2 days before being reintroduced into the company of the aforementioned frisky, sometimes a bit aggressive,  males. If not, a well planted tank, and plastic plants are fine, as well as that higher female to male ratio, helps keep down the stress level of new mothers . Where possible a re.entry time of lights out gives mom a bit of extra time to recuperate. . Depending on what I have in my waiting list of additional expectant mothers, I like to leave my fry in the delivery tank for a day or two. feeding only once or twice the first  day, a diet of live or frozen baby brine is best. There are also prepared dry and liquid foods, my experience is it  more difficult to foul your water by using the brine, but any food can be over used. For that reason, given the average "Drop" of 40-60 fry, I try to feed every 3-4 hours, dissolving frozen brine directly over the sponge filters, to insure the cube breaks up completely, rather then clump at the bottom, this also spreads the food more evenly so any weaker siblings get their fair share of food.

Not later then day three, I like to drain the delivery tank, usually my plastic 5 gallon, by about 70%. .then tilt it sideways, gently into a larger aquarium, of ten to 15 gallons, which has been previously drained enough to allow the 5 gallon to be gently lowered into the rearing tank, sideways, allowing the now free swimming fry to well, freely swim into the larger tank. . By the time your fry are about a quarter inch in length, finely crushed flake foods, and live or freeze dried daphnia, and microworms make  great  additions  to the daily diet, no more then they can eat, completely, in about a minute, two at most.

. As your fry enter their fish puberty, it is a good idea to spread the males out among different tanks where possible. Dominant males tend to diminish the rate of males to females. While this is great for your breeding program, attempting to sell your excess stock to stores with an uneven ratio of males might result in some sales resistance and or lower prices, if not out right rejection of otherwise healthy stock. Bear in.mind a tank of none.;but females, sometime results in a natural sex change of females into fully functional males. Take THAT Jurassic Park, ! Only female dinosaurs indeed ! Remember that movie? Clearly the Jeff Goldblum .character raised swords.