secret to raising sailfin mollies that develop
into big, large-finned adults is food! Mollies
love to eat—they never seem to stop eating,
and they need to eat often. It is nothing to
feed a colony of sailfin mollies or a tank of
their fry five to eight times a day. Mollies
continually graze, and that dietary behavior
needs to be respected when keeping these
fish. Mollies are not fish that you just
throw a bit of flake food to once or twice
a day. In my fishroom, their diet was
built around two very generous feedings
of newly hatched brine shrimp to both the
adults and fry every day.
In addition, the following foods
were alternated over the course of each
week: frozen adult brine shrimp, frozen
bloodworms, a frozen beef heart/vegetable
Many popular hybrid sailfin mollies in the hobby have considerable P. velifera ancestry.
mollies. Nothing else was added to the
water—especially not salt.
In the early 1970s, Dr. Norton explored
the age-old myth that mollies required
salt in their water. She found that salt did
not matter with mollies one way or the
other, but space, water movement, and
cleanliness did. Now, I’d guess there are
populations and/or species of mollies that
do need salt in their water, but the sailfin
species—or, at least, the majority of their
populations and domesticated varieties in
the hobby at present—do not.
On top of the ample living room and
frequent large water changes I consistently
gave the mollies, I provided them with a
rich and varied diet—lots of it. Part of the
Poecilia petenensis, a mature male from the stock of evolutionary biologist Dr. Margaret Ptacek,
who caught these fish in Central America and maintains wild populations in her lab.
Poecilia petenensis, an adult female.
mix, a frozen salmon-based mix, frozen
mysis shrimp, live daphnia, live wingless
fruit flies, live grindal worms, live
microworms, micropellets, algae wafers,
garlic flakes, brine shrimp flakes, beef heart
flakes, spirulina flakes, earthworm flakes,
decapsulated brine shrimp eggs, and an all-purpose tropical fish flake. Also, the sides
of the tanks, as well as the other surfaces
within the tanks, were covered with soft
green algae for the mollies to nibble on.
I fed and fed and fed—which is not the
same as overfeeding. I used portions the
fish could easily consume at each meal in
five to ten minutes. Overfeeding leads to
water pollution and overweight fish.
There were times when I would overdo the
feeding and produce large fish that were far
too bulky for their species. When I got it right,
my reward was a giant, spectacularly formed