Top 5 Tiny Foods to Feed Baby Fish for Healthy Growth

Breeding fish is such a fun and rewarding part of the aquarium hobby, but while it can be easy to get fish to spawn, raising their tiny babies is where the real challenge begins. High losses often occur in the newborn phase because of water quality issues, predation, or simply not feeding enough of the right foods. We will be discussing 5 foods that are small enough to feed even the smallest fry. This will help them grow fast and last for the next few weeks.

1. Baby Brine Shrimp

Peacock gudgeon fry eating baby brine shrimp

Talk to experienced fish breeders and fish farms that raise large numbers of fish, and you will find that baby brine shrimp is the #1 food for fry. Newly hatched brine shrimp have a nutrient-packed yolk sac that is chock full of healthy fats and proteins – perfect for feeding baby fish. The fry will eat more of the brine shrimp eggs to grow faster and stronger because they are a live food. To hatch brine shrimp eggs, you need to soak them in salt water and add aeration by an air pump. Once the water has reached 74-82degF (23-25degC), the eggs will be ready for harvest. Baby brine shrimp can be harvested within 18 to 36 hours. As long as you buy good eggs, the recipe is very reliable, so follow the instructions in this article.

Baby brine shrimp are approximately 400-500 microns in size and are suitable for many baby livebearers, African cichlids, and other species that lay larger eggs. However, if you are hatching tiny fry from egg layers like killifish, rainbowfish, and tetras, the newborns are too little to eat baby brine shrimp. The rest of this article will focus on smaller starter foods. We strongly recommend that you switch to baby brine shrimp once your fry have grown sufficiently.

2. Infusoria

Freshwater plankton under a microscope

Most baby fish in the wild eat microorganisms like protozoans or invertebrate larvae. The range is between 20 and 300 microns. Infusoria, the common name fishkeepers use to refer to freshwater plankton is also used for many other methods of culturing them. A popular technique is to fill a large container with a few quarts or liters of old tank water, mulm, then add in a piece banana peel, catappa leaf, instant yeast or other organic matter. Warm the water to tropical temperatures between 78-80degF (26-27degC) for faster results and add aeration to minimize the smell. The water will become cloudy soon as bacteria begins to break down the food. After that, it will become clear as the infusoria consumes them.

Use a turkey baster or pipette to extract water from the top of the scum. Then, feed the water directly to the fry. Depending on how often you harvest, the culture might last for between two and four weeks. The culture can be extended by adding tank water to the jar, adding food each week, and using turkey basters to get rid of some of the gunk. If you are raising lots of babies and need a constant supply of infusoria, you may need to start a new culture every 1-2 weeks. Just pour water from the old culture into the new jar, add a food source, and fill the rest of the jar with aquarium water.

3. Vinegar Eels

Vinegar eels being harvested in a bottle neck

If keeping infusoria sounds too time-intensive, try your hand at another live food – vinegar eels. This tiny roundworm or nematode is simple to grow and measures 50 microns in diameter. They are 1-2 mm long. Create a mixture of 50% apple cider mixture and 50% dechlorinated water inside a wine bottle or other long-necked container. Add some apple slices and a starter culture of vinegar eels, and wait for them to reproduce. Once you can visibly see them wiggling near the surface, harvest them by adding a wad of filter floss in the neck of the bottle and some fresh water above the filter floss. The vinegar eels will swim towards the fresh water above, so you can easily scoop them out with a pipette to feed the baby fish. Their wiggling motion will attract the fry, and they provide longer access to food since they can survive in fresh water for several days. You can make your own vinegar eel culture that will last for up to six months. Please follow our instructions to learn how to do it.

4. Powdered Fry Meal

Sera Micron fry food

If you do not have access or time to maintain live food cultures, prepared foods are an option to consider. Fry food tends to come in a powdered form that ranges from 5-800 microns, depending on the brand. It is important to offer a variety of diets so that baby fish don’t become nutritionally deficient. Some of our favorite foods include:

Sera Micron Hikari’s First Bite Easy Fry and Small Fish food – Golden Pearls Crushed Flakes – Spirulina Powder – Repashy gel food in the raw, powdered version

Powdered foods tend to float at the surface because of the water tension, so if you are feeding baby bottom dwellers, you may need to swirl the water to get the particles to sink faster for them. We recommend that you use a small children’s brush to avoid feeding too many fish. Dip the bristles in the powder and lightly tap the paintbrush a few times over the fry tank to feed them. This will ensure that you don’t feed too many fry at once, as this can lead to water quality problems.

5. Green Water

Microalgae under a microscope

Although green water looks very similar to infusoria, its size is smaller. However, the color of green is more apparent because it is mostly made up microalgae and other photosynthesis-producing phytoplankton. Hobbyists are usually trying to figure out how to get rid of green water in their aquariums and ponds since it makes it harder to view the fish and plants. But it can have many benefits. It purifies the water and makes it more difficult for adult fish to predate on their younger, heals minor ailments, and provides food for baby fish and daphnia culture. Start with a large jar, aquarium, or other container and fill it with old tank water. To create a rich environment for microalgae, add liquid fertilizer, fish feed, or other organics. A filter, air stone or other device is also useful to help the algae get enough oxygen and carbon. You can shine non-stop 24 hours per day with a light source such as a desk lamp on the container. After several days, the water should start to turn more and more green and will be ready for feeding to the fry.

A Few More Fry Feeding Tips

Baby fish require small meals at least 3 to 5 times per day. Also, it helps to put the fry in a smaller container or aquarium so that they don’t need to swim as far and waste as much energy finding the food. Frequent feedings in smaller containers can quickly cause water to become contaminated and lead to fry death. Therefore, frequent water changes are necessary to ensure that the water is stable and clean. Master breeder Dean addresses this problem by creating a rack of fry trays that constantly drips and circulates water from a larger aquarium down below.

Feeding is only one part of raising healthy fry. Continue reading to discover our top 5 tips for raising baby fish that will grow to be strong and healthy.