Fast or Slow…What D.O. You Know
Possible Procedure
Step 1 Gather specified materials.
Step 2 Obtain 150 ml of aquarium water in the 250 ml beaker. Add a goldfish to this water
using a fish net.
Step 3 Carefully place the thermometer in the 250 ml beaker with the fish to determine the
temperature of the aquarium water the fish is in. After a couple minutes, record this
temperature in the Data Table.
Step 4 Observe the respiration rate of your fish at room temperature. Count the number of times
the gills open and close in 30 seconds. Record the results in the Data Table.
Step 5 Repeat step 4 two more times (same person timing and same person counting gill
movements) and record the information in the Data Table. Calculate the average when
complete.
Step 6 Obtain 200 ml of ice water in the 600 ml beaker. Slowly lower the 250 ml beaker that
has the goldfish and thermometer down into the 600 ml beaker. Wait for the fish’s water
to lower 4° C then carefully remove (slide) 250 ml beaker out of the 600 ml beaker.
Step 7 Repeat Steps 4-5.
Step 8 Return fish to classroom aquarium. Clean up materials.