The art of raising fries to adulthood is, in my opinion, much tougher than getting their parents to spawn. This article describes some highlights in raising betta fries, and in doing so, hopefully can assist first time hobbyists in their breeding attempts.
It is not advisable to feed the male after spawning takes place. Some males are egg eaters and will gladly devour their own eggs. A smaller percentage will even cannibalise their very own fries. Feeding of the male betta after spawning should be avoided as it seems to remind the father how hungry he is and may actually spur him into cannibalism. With proper conditioning before spawning, the male betta should be able to withstand his duty period without food.
Under Singapore's tropical climate, the hobbyist
should be able to witness, in about 36 hours after the
spawning, the hatching of betta eggs. A cooler temperature will increase the incubation period, though all eggs should have hatched by 48 hours. Any unhatched eggs after a 48 hour wait are very likely to be unfertilised and spoilt, and they should be removed at the very first opportunity without disturbing either father or progenies. To the naked eye, newly hatched betta fries appear as little wrigglers within the bubble nest, often with their tails sticking out of the nest. At this stage, the fries wil cling on to the bubble nest. As they struggled in learning how to swim, some fall from their nest and these are dutifully picked up by their father and blown black into the bubble nest.
<Picture of egg mass and newly hatched fries>
In about 48 hours after hatching, the fries should be able to swim horizontally without falling to the bottom of the tank. They are said to have reached the free-swimming stage. So far, the betta fries have been feeding off nutrients stored in their yoke sac. In the next 24 hours, this nutrient stockpile will be exhausted and it is time to start a religious feeding routine. A few betta breeders I speak to, prefer to start feeding about 3 days after the eggs hatched. But I personally start very light feeding about only 60 hours after the fries hatch, simply because I noticed that the early starters of the spawn depleted their egg sacs earlier.
Feeding amount is slowly increased with each feeding. Many first-time breeder lose a large percentage of their fries to starvation simply because no fry food is available at this very crucial period. Examples of fry food are baby brine shrimp, daphnia, microworm, infusoria and other processed fry food. Tubifex and bloodworms are too big for fries at this stage. I prefer to use live food as it seems to entice the baby fries more with their movement than processed food.
<Picture of free swimming fries at ?? hours>
Young fries need a high fat diet to fuel their massive growth rates. Baby brine shrimps fit this bill very well and are easy to prepare. It is therefore the preferred staple food for many hobbyist during the first few weeks. The male betta should be removed when all the fries are free swimming (about 60 hours after hatching). Light medication for its probably torn fins will be helpful.
To sum up what has been said so far, the average betta fry has slightly less than 84 hours between spawning and the need to feed. Bear in mind though that this is just the average time. Statistically speaking, some fries will exhaust their yolk sacs faster than others. To prevent these early starters from starving, light feeding can commence as early as 60 hours after spawning. The optimal amount of feed (for live baby brine shrimps) is the amount the fries can consume within a hour, with a minimal amount of left over. Multiple feedings a day are highly desirable as they encourage fry growth. The frequency of feeding, though, depends really on the availability of time to the hobbyist. But I will recommend a minimum of two feedings a day.
Before establishing the optimal amont to feed, the hobbyist should remain vigilant and remove any leftover food before they decompose and foul the water. The importance of quality water care cannot be overemphasised.
Upon reaching 3 weeks of age, the fries should
be able to consume larger sized food such as the tubiflex
worm. Weaning to a more varied diet can be conducted by feeding successively smaller amounts of their
original food and increasing the amount of the new food.
<Picture of 3 weeks old fries>
The betta fries grow quickly in the first month of its life. A growth rate of 1 mm a day is commonly achieved. At 3 weeks of age, betta fries shold start showing signs of fin growth and suggest their colour potential. The hobbyist will be able to identify any double tailed specimens from the spawn. Young males which exhibit aggressive behaviour, such as consistent flaring, should be removed from the community tank and be individually jarred. With proper care and adequate feedings, the fries should reach marketable sizes and sexual maturity by 4 months of age. Good luck.
<Picture of 2, 3, 4 mth fries>