How often do we read ‘take a pair of fish’ ...?
I maintain it is impossible to be sure of the sex of angels
until the ovaposer is evident just prior to spawning. Often
the fish themselves don’t seem to know since two females
will spawn together and two males will agree quite well
until one has the urge to spawn and then there is mayhem.
A true pair will quarrel viciously, locking jaws and tearing
at each other, so that the bewildered aquarist – fearing
injury to his fish will separate them. Therefore the old
method of obtaining six young fish and allowing them to
select their own partners is still the best and not nearly
such a violent procedure.
Angels do not become mature until ten or twelve months old,
depending on how well they have grown. In my tanks I always
have more females than males and from watching their behaviour
find that the males stand ground in lordly fashion while
the females slog it out. Knowingly my own fish it is possible
to sort them into pairs with a fair degree of accuracy.
Once a pair has been selected they are introduced to a tank
with broad-leaved plants as well a grasses and a piece of
roofing slate is added so that they may have a choice of
spawning sites. The base of the tank is dark with algae
(no gravel) and plants weighted with lead. The temperature
is 80ºF (26ºC). It is useful to have a screen
of plants and a very few small, harmless but bold fish like
platys. The reason being that when the angels spawn they
chase the other inhabitants into the plants where the platys
provide enough threat to keep boredom at bay while the eggs
are hatching. It is no fun guarding young where there is
no danger and often the pair fight because of this.
While angels are courting they communicate by means of clicks
made by their gills. This sound is quite audible as they
seek out a spawning site. The search may take a week or
two but eventually they will spend more and more time at
one spot.
The young angels are now in a learning situation. Often
the first, second and third spawning will be devoured but
usually each spawning lasts longer than the previous one
as the parents gain experience.
Some of the eggs will be infertile and they turn white.
Sometimes the parents will remove these, but not always.
After 72 hours the young hatch and wriggle on the slate
but it will be another five to seven days before they are
free swimming.
Once the eggs have hatched the parents will remove the fry
to a new site, usually a leaf. This can be a very haphazard
operation when an inexperienced pair are involved. It is
not until they have fussed about in a confused manner that
a pattern begins to emerge. One parent carries young to
the new nest while the other remains at the old. When the
mouthful of young have been safely laid on the new leaf
the second fish takes up some fry and with one accord both
parents move so that the returning fish is in sight of the
old site while the parent carrying young has the new nest
in view, thus cutting down the time their fry are at risk.
When the young become free swimming the parents’ rush
about retrieving the swimmers and depositing them on the
leaf, until, from exhaustion, they give up and accept that
their family is mobile. At this point one should take out
the decoy fish.
The young angels now resemble a cloud of midges as they
hover over the head of the parent in charge. The off duty
parent is always alert to assist but only the controlling
parent signals the fry with twitches of the dorsal. If this
is not heeded the straying youngsters is caught up and spat
back into the centre of the group.
The careful aquarist will always put off the tank light
but leave on the room light, so that adults may see to collect
the young into a group which is easily guarded during the
night.
At five weeks the fry assume angel shape and provided they
are fed frequently can reach one inch diameter in twelve
weeks. They accept newly hatched brine shrimp a few hours
after becoming free swimming. A wide variety of food should
be offered as angels become addicted to one type and will
suffer a check in growth when offered different food by
a new owner.
The adults should be removed if they show signs of spawning
again or if they appear to be wearied with the fry.
The parents are very brave and will attack the aquarist’s
hand and siphon tube with quite hard jabs of the snout.
If one can encourage angels to bring up their fry naturally,
there is no more rewarding sight than a flotilla of young
being paraded by proud parents.
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