Breeding

If your guppies are healthy and you have both sexes, you will have fry whether you planned them or not. The good news is that guppy fry are about the easiest baby fish there is to raise, and if you keep them in hard, alkaline tap water like mine, you already have one of the main ingredients for fast, strong growth without buying a thing. This is how I bring guppy fry on from a surprise batch in the morning to young fish you can sex and move on, and the honest limits of what hard water can and cannot do for them. ...

The first time a batch of shell-dweller fry appeared over the sand in one of my tanks, I did what a lot of people do and reached for crushed flake. The fry ate it and survived. Then I tried baby brine shrimp on the next brood, and the difference was obvious within a week: fatter little bodies, faster growth, and far fewer that simply faded away. Baby brine shrimp, or newly hatched Artemia, is the single most useful thing I have added to raising fry, and hatching your own is cheaper and easier than it looks. ...

If you want to breed fish, start with livebearers. Guppies, endlers, mollies and platies do not need conditioning, spawning triggers, egg guarding or artificial hatching. They need a male, a female and water. I keep a line of endler and guppy crosses that has been running for generations in one of my tanks, and my honest job as their keeper is not persuading them to breed. It is deciding what happens to the results. That second part is where this article will spend some honest time, because most breeding guides gloss over it. ...