How to Make Your Own Phytoplankton

Phytoplankton is a microalgae reef food that lives near the water's surface. Phytoplankton is the start of an herbivore food chain ecosystem, which can be used as feed for multiple creatures including but not limited to seahorses, snails and amano shrimp. Phytoplankton also helps filter an aquarium, when the cultures are still live. Home-grown phytoplankton is a cheaper alternative to purchased microalgae products and has a longer shelf life than store-bought algae.

Things You'll Need

  • Wide-mouth two-liter clear plastic jar with plastic lid
  • Drill
  • 1/4-inch and 1/8-inch drill bits
  • 5/16-inch rigid aquarium airline tubing
  • Tape measure
  • Scissors or cutting blade
  • Soft aquarium tubing
  • Clean 5 gallon bucket
  • 4 tablespoons household bleach
  • 4 gallons water
  • 2 liters premixed saltwater solution
  • Saltwater test kit
  • 3 milliliters of liquid all-purpose plant food
  • Starter culture of microalgae
  • Aquarium air pump
  • Fluorescent lamp with 5,700K light bulb
  • Automatic timer (for the lamp)
  • Clean clear two-liter bottle with lid
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Instructions

    • 1

      Drill a hole in the center of the jar lid using a 1/4-inch drill bit. Drill another hole, about 1/2 to 1 inch away from the edge of the lid, using the 1/8-inch drill bit. The large hole will hold the tube; the small hole will allow air flow.

    • 2

      Cut the rigid tubing to a length equal to the height of the jar plus 1 to 2 inches. Cut the soft tube long enough to reach the air pump. You can position the air pump anywhere you like, close to the jar. Place the soft tube over the end of the rigid tube.

    • 3

      Place the rigid tubing through the large hole in the lid. Allow the rigid tubing to stick out through the top of the lid 1 to 2 inches. The majority of the rigid tubing will be inside the jar when the lid is closed.

    • 4

      Soak the jar, lid and tubing in a five-gallon bucket containing a mild bleach solution for two minutes, then drain and air dry. The bleach solution should contain 4 tablespoons of bleach to 4 gallons of water.

    • 5

      Add 2 liters of premixed saltwater solution to the jar. Test the density of the saltwater solution with a saltwater test kit; the test will make sure the water has the correct specific gravity (SG) for the aquarium where the phytoplankton will eventually live. Ensuring a stable SG will reduce possible shock for the creatures already in the aquarium.

    • 6

      Add 3 milliliters of liquid all-purpose plant food to the jar that contains the saltwater solution, then add the starter culture of microalgae.

    • 7

      Assemble the system by placing the lid on the jar and connecting the soft tubing to the air pump. Adjust the air pump until turbulent bubbles are created in the jar. This helps keep the microalgae alive.

    • 8

      Put the lamp with the 5,700K fluorescent bulb in a dark place, such as on a closet shelf. Cennect the automatic timer to the lamp. Place the phytoplankton jar under the lamp. Set the automatic timer to expose the algae to the light for 16 hours and then allow it to sit in darkness for eight hours. Continue this cycle until the algae is green and opaque.

    • 9

      Add the phytoplankton to the aquarium 1 to 2 times each week. Add just enough to give the tank a green tint. Phytoplankton can be stored refrigerated in clear plastic two-liter bottles with lids. If in storage, shake the algae every day to keep the cultures alive.