AqualogNEWS100
11
TrueMidnightMollieswith a red, orange, or yellowdorsal-fin edging arehardly ever seen in the trade.
This is a specimenof
P. latipinna
froma fish farm inSingapore.
many people experience problems with
thesemollies.Howcan thisbe so if,during
visits tomollybreeders andexporters, the
specimens you see are ingreat condition,
withsailfinmales incessantlydisplaying to
each other with fully expanded dorsals,
and with alert, blemish-free fish in every
tank?
Sailfins in thewildarealsoactive,bustling
fish which occur in shoals, where males
are constantly displaying towards rivals
and chasing females. I still vividly
remember such a scene during a visit I
made to an estuarine river in Florida that
was packed with
P. latipinna
. Those fish
were spectacular, to put it mildly. They
were also robust fish which were, clearly,
inpeakphysical condition.
The fact is that sailfin mollies are tough
fish.Thismay sound a little strange, given
the difficulties that many aquarists
experience with them, but it is perfectly
true.Theonlyproviso is that theymust be
kept under appropriate conditions for
them to remainhealthyand robust.This is
wheremost peoplegowrong.
So…who’s toblame for this?
Actually, we can’t point the finger at
anyone inparticular. It’s a combination of
factors that contribute to thedemiseof so
many aquarium sailfins. One of the most
common is that these fish are frequently
regarded as good community fish. They
are certainly mild-tempered enough for
this, but their requirements in terms of
water chemistry are not compatible with
mosthomecommunityaquariumset-ups.
Most sailfinmollies requiremedium-hard
to hard water, temperatures around 25-
28oC, vegetable in their diet and…very
importantly…some salt dissolved in the
water (about one teaspoonful per 4.5
litres or so).The reason for the salt is that
both sailfin species are often found in
brackishwater habitats in thewild; some
are even found in marine conditions,
Further, most commercially-bred sailfins,
especially in some Asian countries like
Malaysia, are kept and bred under
brackish conditions, either in outdoor or
indoor ponds/tanks. Although I have
witnessed this myself many times, I
checked with some of my friends and
colleagues during the preparation of this
article and they all confirmed my
observations (seeAcknowledgements). In
Singapore, though,many sailfins are bred
in
freshwater
indoor
concrete
tanks/ponds.
These methods of breeding and rearing
sailfin mollies mean that such fish must
either be kept under similar conditions in
homeaquaria (dependingon their origin)
or must be acclimatised very carefully to
other conditions. Maintained/adapted
properly, sailfins are active, delightful,
