How to Spawn Bettas
First you will need a male and female Betta. You will have to separate them in two different tanks, around 2-5 gallons. In these tanks you will need a cheap air driven sponge filter or a mechanical filter, a heater, a live plant or two. Gravel, lighting, rocks & whatever you feel needed to make it look attractive. Remember to remove all debris and extra food from the tank to keep it nice and clean.
Second you'll need a breeding tank or spawning tank. Which should be around 5-10 gallons. You will need an air driven corner filter (sponge so the fry don't get sucked up into the filter,) a heater, lighting, and live plants for the female to hide in.
There should be no substrate in this tank. So when the female is releasing her eggs, the male takes them to the nest, and sometimes he may miss a few, and if there is no gravel on the tanks bottom he can search and find them and put them in the nest. The water temperature should be around 80 °F.
Now it's time to condition the male and female Bettas is their own tank. To do this you will have to feed them live food such as live newly hatched Brine Shrimp, and live BloodWorms. Feeding should be 2-3 times a day just as normal. It seems to be if you feed them what you would feed the fry or offspring to the Bettas, they know that there is a significant supply of food for their young, and they will be more ready to spawn.
When two weeks of conditioning has passed, it's time to spawn. First introduce the male Betta into the spawning tank. To do this place the male into a plastic bag and float it in the tank for 20 minutes to allow him to adjust to the temperature. After 20 minute has passed, slowly release the male into the tank, just like you would a new fish.
After a few hours has past, it's time to put the female into a bag. The bag should have about 25% water and 75% full of air. The male should flare at the female and try to attack through the bag, but don't worry it's normal behavior. Leave her in the bag until everything is settled down. By now the male Betta should be constructing a bubble nest, and the female should be taking on her vertical spawning stripes, and should look slightly more rounder than usual. This is the eggs inside of her. Now it's time to release the female just like the male.
Now that the female has been released into the tank with the male. The male should chase the female around the tank for a bit. Again this is normal behavior. The male will now coax the female towards his bubble nest. If she doesn't like it, she will destroy it and make him build a new one. This may take and few minutes, hours, even days.
When she accepts the nest. She will now swim under the bubble nest with her head almost facing the bottom of the tank. This is letting the male know she is ready to spawn. He will embrace her, squeezing her until all the eggs are out, he will then fertilize them as they are being squeezed out. When this has finished, the female will look almost dead from spawning. This is normal for the female Betta. The male will now take the eggs to his bubble nest. This is why there should be no gravel or substrate on the bottom of the spawning tank.
When they are finished spawning, the male will chase the female away from the nest. You should now move the female into her own tank. The male will begin caring for the eggs now. He will keep moving and fanning them. This stops them getting fungus. He will eat the fungus eggs.
When the fry are free swimming, move the male back into his tank. Now it's your turn to care for the fry and feed them. The fry will hatch within 24 hours of spawning.
How to feed the fry
Now the fry has hatched and it's time to care for the baby Bettas. First you'll need food, ofcourse. And lots of it since a Betta fry have atleast100-500 baby Bettas. Many will die out before there born or through the course of feeding them and the process of culling. Tips on how to make Betta fry food read the "How to make Betta fry food" section.
You have just removed the male Betta and your now caring for the fry on your own. You will need to make some food for the fry. This you should have started before you even started conditioning your Bettas for spawning.
First you will need to feed you Betta fry infusoria for a few days while their yolk sacs dissolve. Infusoria or Green Water is a general name for microscopic organisms like protozoa, euglena, etc. This is an excellent source for food necessary for the tiny fry. Feeding green water is easy. Simply put some in the water with your fry.
When their yolk sacs have dissolved it's time to start feeding them mircoworms. This is just slightly smaller than newly hatch Brine Shrimp. Feed them this for a few more days until they grow big enough to eat Brine Shrimp.
When they have grown big enough to eat larger food, it's time to feed them newly hatched Brine Shrimp which you will feed them, with a spoon for easier feeding, until they can eat regular Betta food.
Now that they have grown to a size you have see what gender they are. It's time to cull down your new Bettas. Get rid of the unhealthy Bettas and if you don't want any of the healthy Bettas contact your local pet shop and see if they would like a donation of healthy Bettas, for cash, or store credit. Keep only the Bettas you have room for and that you like and breed them. Remember females can be held together in one tank, just remove the "bully" female if they fight. Also, separate the males into separate jars or partitioned containers.
How to make Betta fry food Infusoria or Green Water
Culturing infusoria, or green water is easy. When you clean the algae off the side of your aquarium, save it in a glass jar, like a medium sized pickle jar or bigger. Place it in the strongest area of sunlight and the maximum number of hours of direct sunlight. You can add water from the little basin under your house plant, as this usually contains many micro-organisms that will flourish in populations in a green water culture. Add to this a small piece of wilted lettuce or a dying leaf from a house plant or an aquarium plant. Putting a few snails in the green water helps to cultivate green water and prevent contamination.
The water is green, because of the chlorophyll in and photosynthesis of the algae and the protozoan consumption of that algae. Occasionally, you will need to start a fresh culture using ¼ of the water from the existing culture as the seed. If the culture begins to smell too fowl, then it's time to start a new one and initial aeration with an airstone, will help slow the growth of anaerobic bacteria cultures that smell foul.
This is another easy culture. Just get some Gerber baby oat cereal, or Cream of Wheat and put it in a small disposable plastic container. Add water and stir into a paste. Add some dry baking yeast to this. You want this thick, because when the culture matures water being the waste of the microworms thins out the medium over time. Add the microworm starter culture, medium included. You can get a starter culture from a fish shop or somewhere that has fish supplies and food.
In about 3-4 days, microworms can be seen moving the surface of the medium. Skim the surface with a toothpick and feed it directly to the fry. In time, the culture will start to turn sour and have a lot of liquid, so you'll need to take a started from this batch and add it too a new batch of medium.
Brine Shrimp (Naupii) Newly hatched Brine Shrimp is high in protein as is good for your grown up fry. You can feed your fry frozen adult brine shrimp but it's not as high in protein. This food can be feed to adult Bettas before spawning in a conditioning stage to help introduce spawning.
Okay this is another easy culture food for your fry but it does take practice to get the maximum yield out of a batch. In a quart jar add 2 tablespoons of aquarium salt or seasalt. Most of the boxes or bags of aquarium salt will have brine shrimp hatching instructions on them. After all off the salt is dissolved, vigorously aerate by adding an airstone, add ¼ teaspoon of brine shrimp eggs, and put a light near the jar. The light in necessary for the nauplii and it also produces heat. Depending upon the temperature (78-80 Degrees F) the nauplii will hatch in about 24-36 hours. After 24 hours or so, remove the airstone and let the water settle. After a few minutes, the darker egg shells will float to the top. Also, nauplii are phototropic so it will be easy to see them swim and to remove them.
Using some air tubing, siphon out the water into a funnel lined with a coffee filter. Be careful not to get too many egg shells and after a few times of doing this, you'll be able to siphon down to about 1/8 to 1/16 of an inch of water remaining, without collecting egg shells. After all of the water has drained out of the coffee filter, you'll have an orange spot at the apex of the filter that when you look at it, you'll see the movement of the nauplii. Invert this filter into a cup or small container with fresh water in it. The nauplii immediately leave the coffee filter. Using an eye-dropper, collect the nauplii and feed the fish.
When feeding brine shrimp nauplii to fry fish, be careful to not overfeed. Using the eye-dropper method helps control the amount you feed, but you can also use a tiny clean paint brush, to take some of the nauplii off the coffee filter to help control the amount you feed to the fry, where there is the best chance you many overfeed. Adding a snail in the hatching tank will help to control problems from left over nauplii.