A Guide on Improving the Growth Rate of Flowerhorn Fry
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.
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.
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.
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.
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.
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.