Growing Your Own Fish Food

Growing Your Own Fish Food

Growing your own fish food is a great way to produce cheap, nutritious food that’s free of parasites. It’s also one of the easier ways to obtain live foods, which otherwise can be hard to find locally.

Here we’ve given a quick guide to growing worms, daphnia and brine shrimp, three of the most common DIY live foods used by aquarists. We’ve also provided you with links to some very helpful how-to videos for setting up your own cultures or hatcheries.​

Microworms and Banana Worms

Microworms and banana worms are an excellent food source for fry, and for smaller fish species such as neons. They’re also some of the easiest live foods to grow at home. Both types are tiny nematodes and thrive in similar culture conditions.

To set up a worm culture, you will need:

  • A starter culture of live worms, which can be obtained from another hobbyist in your local aquarium club or online through venues such as eBay
  • A plastic container with a lid, preferably at least 5” x 5”
  • Oatmeal or instant mashed potatoes
  • Active dry yeast

Setting up your worm culture:

  1. Cook the oatmeal as directed, and layer one inch into the bottom of your container. If using instant mashed potatoes, reconstitute using water only.
  2. Allow the oatmeal to cool overnight or until it has reached room temperature.
  3. Mix in 1 teaspoon of active dry yeast
  4. Add your starter culture to the container.
  5. Place the lid on the container and poke some air holes.
  6. Stir culture once per week.
  7. Worms will be ready to feed in 3-4 weeks.

Tips and tricks:

  • Repeat the above process every 6-7 weeks to turn over your culture.
  • Your culture will crash if you do not turn it over. Most aquarists forget to do this eventually, so a good safeguard is to give starter cultures to a few hobbyist friends.

Please see Aquarium Co-op’s very helpful how-to video for microworm and banana worm cultures.


Daphnia, also known as “water fleas” are small planktonic crustaceans. They make very nutritious food and reproduce quite quickly.

To set up a daphnia culture you will need:

  • A starter daphnia culture, preferably Daphnia Magna or pulex from another aquarist or from eBay
  • A small aquarium or storage bin container (between 5-10 gallons)
  • An air pump, airline and bubbler stone
  • Active dry yeast
  • A light source, either direct sunlight next to a window or artificial lighting

Setting up your daphnia culture:

  1. Age tap water or use dechlorinator to remove chlorine. You can also use water from your aquarium.
  2. Fill your container with water.
  3. Put the air pump on the lowest possible setting, such that water is gently aerated.
  4. Add your daphnia starter culture.
  5. To feed, mix yeast and water in a separate container, and add just enough for the water to be slightly cloudy. When the water is clear again (usually a few days) add another small amount of yeast.
  6. Change at least 20% of the water weekly.
  7. Harvest daphnia with a fine net to feed.

Tips and tricks

  • It may be best to have at least two cultures of Daphnia or to give a starter culture to a friend. This is a safeguard against your colony crashing.
  • Do not allow your colony to become overpopulated. Be sure to harvest often, even if you do not need to feed your fish.
  • Make sure that your culture receives 6-8 hours of sunlight or 10 hours of artificial light.
  • The ideal water temperature for Daphnia is 72-85 degrees.
  • Optimal pH is 6.2-8.9

Please see Glen Thode’s very helpful how-to article for Daphnia cultures.

Brine Shrimp

Young brine shrimp are highly nutritious food for fry or small fish species. They are easy to hatch, and the eggs are sold in dry form, so are a bit easier to attain than starter cultures of Daphnia or microworms, and you also do not need to maintain a constant culture.

There are a few setups for hatching brine shrimp. We’re going to cover how to hatch them in a mason jar, which provides a very convenient setup.

To hatch brine shrimp, you will need:

  • Brine shrimp eggs
  • A one-quart mason jar with metal lid
  • Screwdriver and hammer or punch tool
  • An air pump, flexible airline and bubbler stone
  • 2-3 way gang valve
  • Rock salt or any other non-iodized salt
  • Baking soda or commercial buffering agent if you have soft water
  • Turkey Baster

Setting up your brine shrimp hatchery:

  1. Rinse your mason jar, or if it has previously been used for another purpose wash it thoroughly.
  2. Screw the lid onto the mason jar firmly.
  3. Punch a hole in the center of the lid that is just big enough to pass the airline through.
  4. Punch four smaller holes in each quadrant of the lid.
  5. Put airline tubing through the lid, and cut it to an appropriate length to reach the gang valve.
  6. Connect gang valve to an air pump.
  7. Fill the mason jar with 16 ounces of dechlorinated tap water
  8. Add 3 teaspoons salt. Water pH should be at least 8.0. If you have soft water, add baking soda or a commercial buffering agent to raise the pH.
  9. Dissolve salt and add ½ teaspoon of brine shrimp eggs and turn on the air pump.
  10. Eggs will hatch within 12-18 hours.
  11. To feed, turn the air pump off, allow shrimp to settle and harvest with a turkey baster.

Tips and tricks:

  • Some aquarists use a light source, and others do not. Ambient lighting in your home is likely sufficient.
  • Brine shrimp are most nutritious when they still have an attached egg sac. Ideally, feed within 24 hours of hatching.
  • If you have a poor hatch rate, try slightly increasing your salinity, and make sure that water pH is optimal.

Please see Lincoln Coleman’s very helpful article for more information on hatching brine shrimp.

Have any insights, tips or tricks on growing your own fish food? Please leave them in the comments section!