In this blog post I am going to discuss the different ways to breed guppies and a few tips and tricks to not only breed lots of guppies but also to keep strain pure and keep the quality high.
First of all, let start with the basics. Guppies are live bearers, meaning that the females give birth to live fry instead of laying eggs. The male inserts their male reproductive organ called a peduncle into the female’s vent. The female can store sperm from the male for very long period so if a male has ever been with the female it most surely is pregnant. The upside of this is that they usually have lots of babies, the downside is that they will eat their fry. So whichever method you use, you need to protect the fry from adults. This can be done by either providing cover for them to hide or removing them from the tank and placing in another, the choice is yours. The basic water requirements that suit breeding guppies, is water about 25 degrees C and nice hard clean water. The hotter the water (to 32c) the faster the fish will grow but also the shorter their life expectancy and the weaker the fish generally is.
Diet wise the best thing by far to feed them is live baby brine shrimp. They will literally eat it until they explode if you let them; their instinct to eat the live food is that strong. I also like to feed crushed flake so that I make sure fry get all the vitamins and minerals they require. For adults I feed Flake and Repashy gel food daily with Blood worm, Adult brine, and Baby brine several times a week.
While guppies are relatively easy fish to breed and generally all you need is a male and female, it takes a lot of time and effort to grow the high-end fancy strains such Dumbo Ear, Bluegrass and Albino strains. Some of the newer strains coming out of Thailand are near on impossible to breed pure and involve a lot of culling, I will explain the reasoning behind this later.
When you look at long established pure strains they generally breed fairly pure and require very little culling, but you must keep an eye for those unusual fries that will inevitably pop up and cull or remove them as soon as you see them so as to not taint the strain. Although there are exceptions to that rule with yellow being one of the hardest colours in guppies to keep "clean". They are generally well suited to colony breeding either in ponds (in warmer climates) or a large tank. The main thing you need to do to get lots of fry, is to provide cover for them to hide so the parents don’t eat them.
Strains that tend to have a lot of “throw offs” are better suited to pair or trio breeding and line breeding as this will give you more control over the genes of the fish and stop those strains become a mess. Line breeding is a form of inbreeding which involves starting off with a pair or trio, removing their fry and separating sexes of the fry so that the females are what we call "virgin females", this means you control who impregnates them. Once the fry are of a decent size, you pick the best few females and put them back with their Father and pick the best male and put them back to their mother. Inbreeding this way instead of Breeding brother and sister together is much safer and helps prevent deformities that develop when the gene pool becomes shallow. Eventually though, no matter what type of line breeding you do, you will need to out cross to another line or strain. If you want to breed a strain long term without having to bring in "new blood" then you will need to run multiple lines of the same strains at the same time or get ones from a very similar trusted line, then cross them when a line becomes weaker, smaller or deformed. The other way to do this is out crossing to a different line and while this can be easily achieved with some lines, in others, it can be quite difficult and complicated.
Lastly, some of the new strains coming out of Thailand are very hard to breed and keep pure. The main reason for this is due to the fact the breeders are creating the strains so quickly to bring new ones to the market, that the strains haven’t been bred enough generations to stabilize the genes (also some genes are just naturally unstable). I have heard from some people that have to cull 2/3 or more of a batch of fry in some cases with these lines. The strains are better off left to experienced breeders as it can be rather discouraging for a new comer to the hobby. In the defense of these breeders some of the strains they have been able to produce have been amazing and have rejuvenated the hobby and made it very interesting again to lot of people that weren’t interested before.
The other type of breeding you can do is to create your own line. This can be done by line breeding as explained above, just by using males and virgin females from two different strains. This can be a fun and interesting exercise and to the beginner, it may seem like you get a whole bunch of random colors and/or types of guppies when it reality if you read books written by Phillip Shaddock or similar, and have a good understanding of the guppy’s extensive genealogy, then you will have a fair idea of the outcome, there for you will be more likely to get the result that you desire to get.
I hope this has answered some of you questions and put you on your way to breeding quality guppies. As always if you have any questions please send them to firstname.lastname@example.org or visit our website or Facebook page.