Betta Fish Breeding Step 5 : Live Foods For Fry and Juviniles

The following are the live foods we use to feed our baby bettas. The bettas are fed each food until they reach the size where they can eat the next food up. This diet also works for other carnivorous fish, including angels! We only feed our fry and juveniles live foods as we find anything else slows their growth and their final finnage quality.


Microworms are small nematodes. They are suitable for just-hatched fry, and can be used up to 2 weeks of age, although at one week baby brine shrimp (BBS) should be added to the microworms.

Some breeders skip the microworm stage and go straight to BBS. However, we feel microworms have a limited use that shouldn’t be rejected.

Microworms are easily cultured. In a small plastic container with a lid, put in about 1 inch of Gerber Baby Food Oatmeal – it comes in a box, and is just dry oatmeal. Add in some water and stir until the substrate has the consistency of pea soup. Put the starter culture on top of this mixture, and lightly cover with dry yeast. The microworms eat the yeast, and within a couple days you’ll see the microworms crawling on the sides. Take a q-tip and wipe the sides of the container to collect the worms. Afterwards, swirl the q-tip in the spawning tank to feed the babies. Every once in a while, add more yeast to the microworm culture to keep it thriving. If you see the culture starting to die off, you can subculture using the same directions.

Microworms will quickly dirty a tank if fed incorrectly. Feed enough for the babies to have some left over, but don’t feed two times a day if they don’t need it. Feed when there are very few microworms on the bottom of the tank.

Baby brine shrimp:

Baby brine shrimp are artemia. If given the chance and fed correctly, they will grow into adult brine shrimp which are suitable for older fish, although they are not nutritionally complete for adults.

Baby brine shrimp can be fed to newly hatched fry, up until around one month, or until everyone in the tank can eat grindal worms, the next food.

To hatch brine shrimp, fill a 1 gallon container (we use square or round containers with a screw on lid) with freshwater. Add in enough aquarium salt or Instant Ocean till you have a specific gravity of 1.020-1.040. Brine Shrimp Direct says a specific gravity of 1.018 is enough, but we’ve had greater success with 1.040.

Put in enough air line hosing so it reaches the bottom. The airline hosing needs to be attached to an aerator. The constant movement of the water helps the brine shrimp hatch.
Add in just enough BBS eggs to feed the fish for one day. BBS retain their nutritional value for about 12 hours. We use 2 containers – one for a morning feeding, one for a night feeding. After each harvest we add in enough eggs for one feeding.

BBS will hatch in 24-36 hours. Heat will accelerate the hatching, but isn’t required to have a successful hatch.

To harvest BBS, take out the airline hosing and put a flashlight to the side of the container. The hatched eggs will float to the top and the BBS will be attracted to the light and congregate in one area. Take a turkey baster and suck up the BBS. Run it through a coffee filter, letting all the water drain out. Rinse in fresh water, then dump it into the babies tanks.

Once a week, run all the BBS water through a coffee filter after harvesting. This will remove all the hatched eggs, infertile eggs, and dead BBS so your ammonia won’t spike. Change the water when you notice the hatch out rate decreasing – that means the ammonia has risen higher than the BBS can tolerate.

Grindal worms:

Grindal worms are small white worms. They are about 3/16 – 3/8 of an inch and can be feed usually when the fish are ¼ of an inch long. White worms are related to the earthworm, and are very prolific.

To culture grindal worms, get a plastic shoebox (the more surface area the better) and fill it about ½ full with potting soil (fertilizer free!). Wet it down till its damp, but not sopping wet. Spread the starter culture out on the potting soil, cover the culture with fish flake food or baby food, and spray the food until damp. Grindal worms like damp food much better than dry food.

To collect, take a piece of flat glass or acrylic, sprinkle a little food on there and spray the food until damp. Don’t get the food so wet that it will slide off the collection plate. Lie it flat on top of the grindals. Within 45 minutes worms should have collected on the plate. Leave the plate there until you’ve collected enough food for one feeding.

Holding the collection plate over a container of fresh water, take the turkey baster and pour water over the worms. Try to get as little flake food and dirt in the water as possible. Then, you can either pour the water directly into the babies tanks, or suction out the worms with the turkey baster.

White worms:

White worms are relative of the grindal worms – only much much larger. They can get up to one inch, and both large fry and adult fish. However, white worms have a high fat content, so cannot be the sole food for adults!

White worms are culture the same way grindals are. However, because white worms are much larger and slower growing than grindals, a much larger shoebox or sweater box is recommended.

White worms can also be collected the same way as grindals, or you can hand pluck the white worms from the substrate.

White worms begin to die off around 80 degrees Fahrenheit, so they need to be kept in a cool area of the house or else placed in a Styrofoam box with an bottle of ice to keep them cool.

White worms can be fed flake food or baby oatmeal.

White worms can be fed in conjunction with blackworms, and make a great diet. Blackworms provide complete nutrition for adults, and since juvies do well with more fat content than adults, white worms provide the extra energy for growth.

California Blackworms:

Blackworms are large segmented worms that grow up to a couple inches. Juvies can get either chopped up blackworms or whole blackworms.

It is not practical to reproduce blackworms in your aquariums. It takes several months for a blackworm population to double in size in the average aquarium. They are grown by aquatic foods, who utilizes large pond-like structures and feed them a special high-protein food.

Blackworms can often be found at local pet stores, or can be ordered from . Blackworms need to be kept in the refrigerator. Just barely cover them with fresh water. Because blackworms aren’t fed anything, they need to be kept chilled to slow their metabolism. Rinse them every day with fresh water.

Other foods:

We don’t use these foods, but many other breeders do!


Daphnia comes in many sizes. It requires much more care than brine shrimp. More information can be found about it at

Vinegar Eels:

Vinegar eels are supposed to be very easy to culture. They feed the same size fry as microworms, but unlike microworms they swim around and therefore may be easier to see for the baby bettas. However, it takes a month for a starter culture of vinegar eels to be ready to harvest, as compared to a few days for microworms. Microworms are also easier to harvest. More information on vinegar eels can be found