Rasboras aren’t livebearers. They lay eggs to reproduce, which the male fish then cover with their seed. Rasbora eggs float from the top of the tank, sticking to the leaves bottom while incubating. Rasboras typically lay between 25 to 100 eggs at a time. The fry hatch within 24 hours.
If you want your rasboras to reproduce, it’s important to ensure that the tank conditions are ideal. This means having enough plants and females in the tank for reproduction. Continue reading to discover everything you should know about the breeding of rasboras.
Do Rasboras Deliver Live Fry?
Rasboras, unlike guppies and platies, aren’t livebearers. Instead, rasboras lay eggs, and the babies hatch outside the female rasbora’s body.
Harlequin rasboras are the only rasboras who don’t scatter their eggs at the bottom of the tank. Instead, they deposit their eggs on the underside of broad aquarium leaves, where the eggs stick until the fry hatch.
Other types of rasboras generally scatter their eggs at the bottom of the tank, and the fry hatch from there. Breeding with rasboras is known to be difficult because the rasboras require perfect tank conditions for breeding.
The water must have the perfect pH levels (6.8 to 7.8), and the rasboras require soft water free from harsh chemicals and metals. Furthermore, the water temperature must be perfect for the rasboras to breed. Rasboras require water temperatures of 82.5°F for mating.
How Do You Know When Your Rasboras Are Ready To Breed?
There are a couple of clear indications that tell you when a rasbora female is ready to breed. Some people mistake a bloated rasbora for one filled with roe. Therefore, it’s important to know the different between them.
A bloated rasbora will have a huge abdomen, but it will look smooth. The rasbora will also be slightly sluggish and may refuse to eat.
On the contrary, a gravid rasbora has plenty of energy and will eat the same as, or more than, she normally does. Rasboras that are ready for breeding also may have lumps in their abdomen, where you can see the eggs inside.
Once you determine that your rasbora is gravid and not just bloated, you can proceed with getting the tank ready for breeding.
How Do Rasboras Breed?
When you notice the abdomen of one or more female rasbora becoming fuller, and the rasbora starts eating more than usual, you can assume that the females are carrying roe inside their abdomens. This is an excellent sign that it is time to remove your rasboras from the main tank for mating.
Place one female and one male rasbora in a breeding tank with a dark substrate and ample broad-leafed aquatic plants. This is their preferred breeding ground in the wild and is where they will have the most success.
Place the fish in the breeding take in the late evening, as they usually start mating early in the morning. First, the male rasbora will “dance” for the female to draw her attention. Then, they will swim in a synchronized pattern before turning upside down at the bottom of the leave and depositing some eggs.
The female rasbora will usually deposit around 6 to 8 eggs. Then, the pair will swim away from the leaves and do more synchronized swimming before returning to the plant and depositing more eggs.
Rasboras typically lay between 25 and 100 eggs. When the mating ritual has finished, you can remove the adults from the breeding tank to prevent them from eating the eggs.
How Long Do Rasbora Eggs Incubate?
Once inseminated, the rasbora fry will typically hatch about 24 hours later. If you’re lucky, most of the fry will hatch. The fry stay on the underside of the leaves for about 48 hours or until they have absorbed their yolk sack.
The breeding tank’s water conditions need to be perfect for the fry. If the water is too hard, the eggs may evaporate, or the fry won’t hatch. Moreover, the eggs may not stick to the leaves (in the case of harlequin rasboras), and they won’t develop fully.
How Do You Care For Rasbora Fry?
Because of their incredibly small size, you must keep the fry separated from the group tank for the first month. The fry can only consume infusoria for one to two weeks after hatching.
You can also feed them egg yolks pushed through a fine sieve if you cannot find infusoria during this time. Once the fry are about two weeks old, you can start feeding them baby brine shrimp, and high-quality flake food can be introduced later.
When the fry are big enough that they won’t get eaten by the adult rasboras or other fish, you can move them to the community tank. The fry will reach full maturity in about 6 to 9 months when they are also ready to start reproducing.
You can tell the male and female rasboras apart by looking at their fins. Males tend to have brighter coloration around their dorsal and caudal fins, while females are more uniformly colored. When the females are full of roe, their abdomens are also more swollen and they appear bigger than the males.
Will Rasboras Eat Their Fry?
Rasboras may eat their fry and eggs if they are still small enough. While adult rasboras aren’t known for aggressively feasting on their eggs, they will occasionally consume a few eggs if you aren’t careful.
Therefore, removing the adult rasboras from the breeding tank is best soon after their mating ritual has been completed. This will increase the number of fry you can possibly have.
Furthermore, adult rasboras and other fish in the tank will eat the fry if they are small enough to fit in their mouths. Rasboras are omnivores and won’t think twice about eating their young if they are hungry or bored.
Therefore, you must ensure that the rasbora fry are big enough not to be eaten before removing them from their breeding tank. While in the breeding tank, you must replace 10 percent of their water with water from the group tank to acclimate them to the larger tank conditions.
The rasbora fry should be big enough to move to the group tank when they are about 1 or 2 months old. Some rasboras grow faster than others.
For example, harlequin rasboras are fully mature at about 3 months. In contrast, other rasboras take between 6 and 9 months to fully mature.
How Often Do Rasboras Reproduce?
Under the right conditions, rasboras will reproduce frequently. You can ensure that the conditions are suitable for them to reproduce by increasing the tank’s water temperature and feeding the rasboras a highly nutritious diet of protein and other nutrients.
Furthermore, you must ensure at least two females for each male in the tank. These conditions will encourage the female rasboras to produce eggs, and the mating process will occur naturally from there.
If your rasboras are cared for well, there shouldn’t be any reason for them not to reproduce. However, suppose you don’t ensure the perfect breeding conditions for your rasboras. In that case, they will have difficulty reproducing, and you may never get fry.
Conclusion
Rasboras aren’t livebearers and instead lay eggs. The females will produce roe if the tank conditions are ideal for breeding. Then, the females will indicate that they are ready to spawn, and the males will seduce them.
When the females release the eggs, the males will cover them with their sperm. The eggs incubate for about 24 hours, and the rasbora fry should reach maturity within 3 to 9 months of hatching, depending on the type of rasboras you breed.