Freshwater

Dealing with aggressive males
Some males are naturally more aggressive (actually nasty is the word we were
looking for) than others, and it’s difficult to determine an individual’s habits
before you see him in action. We’ve had very peaceful males of one species,
only to turn around and end up with one of the same species that was ready
to take on Mike Tyson. The only way to tell how aggressive a male is going to
be during breeding is to keep a close eye on him once he is introduced into
the spawning tank.
If your spawning tank is heavily planted and contains many safe areas where
a female can hide, you may be able to introduce both partners at the same
time. We personally do not use this method very often because we’ve seen
too many females torn up by normally peaceful males that got a little too
excited. Be safe and use a partition to allow them to get to know each other
first.
Setting up the second date
If a spawning pair seems to get along well on the first date, it’s probably safe
to put them back into the same spawning tank at the same time. But fish in
love can be very unpredictable, so don’t bet the farm on their getting along
again. It never hurts to use a partition more than once.
Yay, my fish really like each other!
If your fish are having a real romantic picnic, why spoil the fun? Let them
continue to breed as long as they’re in good health. If you don’t want anymore
newborns, keep them in separate main tanks.
Darn, my fish hate each other!
Chapter 20: Let’s Spawn!
If your fish are throwing gravel at each other, they probably won’t be in
the mood to mate. Don’t force something that isn’t meant to be. Give them
a little time away from each other and then try again. If they still try to kill
each other, forget it and work with a different set of partners. We have witnessed
a couple of instances where one male would refuse to mate with only
one particular female out of a group of ten identical-looking fish! Why they
seem to turn on one individual is unknown. A bit of fin nipping during spawning
is normal in many species such as the beta. Just make sure they are not
seriously injuring each other.
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