A Guide on Improving the Growth Rate of Flowerhorn Fry
Population Density
A big challenge that comes with breeding flowerhorns is
making the fry grow as fast as possible. While it is more important to focus
more on producing high quality fishes, this aspect of the breeding process is
equally important.
Scope
This guide deals with fishes from their wriggler stage (when
the eggs are hatched) until they are 2 months old. These fishes are still kept
in community tanks.
Juveniles that are “groomed” in individual tanks are not
included in this guide. My next article will deal with those juveniles.
Food
Among the different types of fry food, my favorite is the
daphnia. However, this type of food is not readily available all year
round. As an alternative, I use pulverized flowerhorn food. There are those
that are especially formulated for smaller fishes. You may use those as well.
Does it have to be
especially formulated for flowerhorns?
No, it does not have to be. I’ve used feeds intended for
goldfish and other cichlids. The results are just the same. Of course, using
those containing higher protein content would normally enhance flowerhorn growth. You also
don’t need to use those containing color enhancers. As long as the feed is
within your budget, you may use it. Feeding a thousand flowerhorn fry with
expensive pellets is just not logical especially that most of them will be culled
anyway.
Culling
Yes, culling plays a big role here. Space is very important
to speed up growth. Whenever, you see fry with visible deformities, I recommend
culling them right away. You would want to provide the high quality ones with the
best possible conditions, e.g. more space, less competition. I do this at least
once a week.
When the fishes are already one month old, I would already
start separating fast growers. Typically, I would prepare an additional 50
gallon tank for this. I would transfer around 100 fast growing fry, each
inspected that they have no visible deformities, to provide more room for remaining
smaller ones to grow.
For a population of 1000, I would typically cull 800.
The remaining 200 will be observed for any sign of head growth in small individual tanks.
Population Density
To really speed up growth, I recommend using the ratio of
100 1-inch fry per 50 gallons of water. Remember that the important thing here
is not tank size. You should focus more on population density. Again, you need
to separate the fast growers from the smaller ones to provide them the
chance to catch up. Never allow fast growers bully the weaker ones. Not all high
quality flowerhorns are fast growers, so you really need to protect slow
growers as well.
Water Change
What if you have a limited number of tanks or your tanks are
not that large?
I’ve seen breeders raise as much as 500 pcs 1-inch fry in 50
gallon tanks and would just do fine. However, they would have to do daily
partial water changes to keep them healthy. Some even do it multiple times
each day. This is fine if you are in a place with unlimited free running water
and you have the time to do this process religiously. Your fry could really
suffer if you could not keep up. 500 pcs flowerhorn fry are always bound to
produce a lot of waste even in just a single day.
If you have enough space or tanks available, I recommend using
the 100 fry to 50 gallon tank ratio. It’s much safer and their chance of
survival is much higher.
How to determine if
you already need to do partial water change?
A good sign that water parameters are not ideal anymore is
when you notice your fry breathing near the surface. At this point, oxygen
level is already very low or ammonia or PH levels are already bad. I don’t
recommend that you wait for this to happen. Instead, create a schedule for
water changes. For fry, I suggest doing it at least once a week.