Freshwater

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Part IV: Breeding and Other Fun Stuff
Following are a few physical reasons why fish won’t spawn:
Their water looks like a sewer.
Their tank is too small.
They need more fish (for example, neons mate more often in schools).
One of the partners is cradle-robbing, or is older than dirt.
The fish have not been fed live foods prior to spawning.
The fish may be sterile.
You have two females in the spawning tank (not good).
You have two males in the spawning tank (even worse).
They just don’t feel like it.
If the problem seems to be mental, check out Chapter 19 for tricks to get your
two fish to like each other. Unfortunately, there are no fish psychologists to
help you along, so if these tricks don’t work you may as well forget it and try
another pair.
Understanding Breeding Types
Fish reproduce in one of two basic ways. Livebearers bear live young.
Egglayers lay eggs. Each type of breeder has special requirements.
Livebearers
Livebearers give birth to free-swimming young that are fully formed and
resemble tiny adults. A female livebearer is internally fertilized by her partner
and carries the fry internally for about a month (called the gestation
period) before birthing them. Immediately after entering this world, the
young fry swim and search for food.
All livebearing fish are either ovoviviparous (the female produces eggs that
contain yolk to feed the embryo) or viviparous (the young are nourished by
the mother’s circulatory system). Ovoviviparous females tend to lose their
brood to miscarriage more often than viviparous ones.
How to tell male from female
A few well-known examples of livebearers include guppies, swordtails, mollies,
and platys. Most livebearers are brightly colored and make great community
fish. It is easy to determine the sex of most livebearers because the