Fish and plants as partners

Students will

• Explain that in aquaponics, fish waste becomes plant food.
• Name the main parts of an aquaponics system: fish tank, pump, pipe, grow bed, and the way back.
• Describe what the plants give back to the fish.

New words

aquaponics

Growing fish and plants together, so they share one loop of water.

Talk about it

Think of a trade where everyone gives something and gets something back. Who would miss out if one partner left?

Check questions and answers

1. In aquaponics, where does most of the plant food come from?

   • Fish waste, changed by tiny living things (answer) Right. Fish make the waste, and tiny living things turn it into plant food.
   • Plant food that people add to the water Not quite. That is how hydroponics works. Here, the fish make most of it.
   • The stones in the grow bed Not quite. The stones hold the roots up. The food starts with the fish.

2. What do the plants give back to the fish?

   • Cleaner water (answer) Right. Roots take up the plant food, so cleaner water flows back.
   • Fish food Not quite. People feed the fish. The plants clean their water.
   • More waste Not quite. The plants take in what the fish leave behind.

3. What moves the water up to the plants?

   • The pump (answer) Right. The pump lifts water from the tank up the pipe.
   • The fish Not quite. Fish swim in the water, but they can't lift it.
   • The roots Not quite. Roots drink water, but they can't lift it up a pipe.

Teacher note

This lesson needs no live fish. If your class keeps fish, follow your school's animal policy.