Keywords: aquarium, tank, heater, floating thermometer, undergravel filter, plastic air tubing, air pump, gravel, plastic screen, plastic bucket, log book or chart, fish food, nitrate test kit, pH test kit, algae scraper, dissolved oxygen test kit, guppies, swordtails; Lesson Plan Grade Level: third grade and up; Total Time Required for the Lesson: three class periods over a month, plus daily feeding time, daily record keeping, and some time each week for maintenance; Setting: indoor classroom

Goals for the Lesson

  • The student will study how living models can help them to understand and relate to the real environment.
  • The student will read and practice following directions.
  • The student will measure temperatures.
  • The student will learn to use different kinds of test kits (nitrate, pH, dissolved oxygen).
  • The students will create a model of an aquatic habitat as a group and be responsible for the upkeep and maintenance of the tank.

Materials Needed

  • a 20- to 30-gallon tank
  • large plastic bucket
  • heater
  • floating thermometer
  • undergravel filter the size of the tank
  • plastic air tubing
  • medium-sized gravel
  • clean rocks
  • tropical fish food
  • plastic screen (large enough to cover the top of the tank)
  • air valve
  • air pump
  • plant grow light
  • log book or chart
  • two guppies or swordtails
  • three or four rooted water plants
  • test kits for nitrates, pH, dissolved oxygen
  • air lift columns

State Standards Addressed: E & E: Ecosystems and Their Interactions (4.6); Science and Technology: Inquiry and Design (3.2) and Biological Sciences (3.3); Reading, Writing, Speaking, and Listening: Reading Critically in All Subject Areas (1.2); Mathematics: Statistics and Data Analysis (2.6)

Teaching Model: Teacher-Directed Class Project

Subjects Covered: science, reading, math

Topics: reading, measuring, organizing, collecting data


  1. Rinse the tank with warm water and non-iodized salt. (Do not use soap of any kind because it will kill the fish.)
  2. Choose a location for the tank that is away from heat and not in direct sunlight, and has an electrical outlet close by.
  3. Put the undergravel filter into the tank and the airlift columns.
  4. Put the gravel in the plastic bucket and rinse it with water. Pour off the water and carefully spread the gravel over the undergravel filter making it about one inch deep. If you have some gravel from an established aquarium it would be a good idea to add about one cup of the gravel to the aquarium you are setting up.
  5. Gently add the water so as to not make a hole in the gravel. (It needs to be water that has been open to the air for at least twenty-four hours) Fill the tank about half full.
  6. Add the clean rocks.
  7. Connect the plastic air tubing to the airlift columns and air pump, then plug the pump in.
  8. Add water until the top of the airlift column is covered, and adjust so that there is an even air flow.
  9. Now it is time to put in the heater and floating thermometer. (If you are using freshwater tropical fish it will need to have a temperature of 76 degrees, or if you are using temperate freshwater fish it will need to have a temperature of 65 degrees.
  10. Allow the aquarium to sit for a day and monitor the temperature from time to time and adjust the heater if needed.
  11. Allow the tank to sit with the air pump running for at least twenty-four hours to be sure the water is clean and clear.
  12. When the temperature is ready, add three to four guppies or swordtails, two crayfish, and three to four snails.
  13. Wait two weeks, and check the nitrate level, then drain off about one-third of the water and add water that has aged in the bucket for at least two days. You can also add some more fish or animals to the aquarium.
  14. Wait two more weeks, then add some plants (like Anacharis) and some more fish and animals like algae-eaters. At this point, the amount of water changed weekly should be reduced to about one-fourth of the total amount in the tank.
  15. Remember to feed the fish daily with just a small amount of food (about what they will consume in five minutes) and remove any dead or dying organisms.
  16. Check the temperature daily and record it in the log book or on the chart. You will need to log time of feeding, temperature, and any changes that were observed.
  17. It is a good idea to measure and record the data from the test kits before doing a water change each week.


Observe the students that are taking turns to do the daily and weekly care of the tank and fish. Discuss what is happening and why they think it is happening. If they notice changes can they tell why the changes are taking place.


Pennsylvania Aquaculture (a booklet compiled by Norma Saylor)

National Aquarium in Baltimore


Norma Saylor, third grade teacher, Williamsburg Community