Procedures

Aquariums


Aquarium set-up

1. Clean six tanks with fresh water and a soft cloth sponge

2. Add tap water to each tank an inch below each rim

3. Add two inches of cleaned gravel to each tanks

4. Assemble a ten gallon filter for each tank.

5. Place the filter on each tank

6. Let the filter run for 2 weeks

7. Add 1000mL (2 -500ml beakers) of dry marine salt to each tank

8. Let stand for one week

9. Use the hydrometer and test the water’s salinity

10. If salinity is too high, add more water. If salinity is too low, add more salt and re-test. The salinity level (specific gravity) should read between 1.021 and 1.025 (inclusive)

11. Test the pH. The tanks should be between 8.0 and 8.4 (inclusive)

12. If the pH is too high, add pH down.

13. If the pH is too low, add pH up (pH should be between 8.1-8.4, inclusive).

14. Test the temperature. The temperature should be between 20 and 25 degrees Celsius.

Maintaining the Tanks

1. Test and record the pH levels of each tank one to two times a week. The pH should be between 8.0 and 8.4 (inclusive)

2. Test and record the salinity of each tank one to two times a week. The salinity should be between 1.021 and 1.025 (inclusive)


Chemical Information

Chemical Safety

1. During the experiment the chemical salt will be used in accordance with the MSDS which states the chemicals used in this experiment are potentially hazardous

2. The use of all chemicals will be performed wearing gloves, aprons, and goggles

3. All chemicals that release fumes will be placed under the fume hood to prevent the release of fumes into the classroom

4. A fire blanket, fume hood, fire extinguisher, eyewash station, and shower are available for use

5. Upon leaving the lab, hands will be washed and all chemicals will be locked in a ventilated storeroom.


Chemical Disposal

Acetone –

1. According to the MSDS, less than 500 mL – at a time – of the chemical is to be poured into a glass/metal pan and allowed to evaporate in a fume hood

2. The pan will then be run through a dishwasher
Ethanol –

1. According to the MSDS, the ethanol will be diluted with 10 fold (not exceeding 100 grams of chemical at one time) water, if sinks are connected with a sanitary water system

2. Do not put combinations of materials down the drain

3. Chemical must be completely dissolved before pouring down the drain

Sodium Chloride –

1. According to the MSDS, the Sodium Chloride will be sent to a local landfill

2. Chemicals will be kept in separate packages, making sure not to mix


Electrical Safety

1. Limit the use of high powered devices around water

2. Never use frayed or cut wires when plugging in a device

3. Never overload the outlet

4. Use a surge protector

5. All electrical devices will have an emergency cut off switch

6. Shut off and unplug all when hot or upon leaving the room

Applying Independent Variable

Creating and applying the EMF Generator

1. Cut a piece of ½ inch PVC pipe 10 inches long

2. Wrap 12 gauge copper wire around the pipe one hundred times

3. Cut another piece of ¾ PVC pipe 12 inches long

4. Glue a ¾ cap on one end of the ¾ PVC pipe

5. Insert the PVC wrapped wire into the capped PVC pipe.

6. Connect one of the wires to the negative side of a variable voltage supply.

7. Connect the other to wire to a voltmeter in series and to the positive side of the variable voltage supply

8. Turn the variable voltage supply on low.

9. Using a gauss meter, measure the EMF emitted from the side of the PVC pipe

10. Adjust the voltage to change the EMF field to create a high level reading on the gauss meter (10 mW/cm^2)

11. Place the EMF apparatus an equal distance from each alga sample within the testing tanks (2, 4)

Tanks 1 and 3 are to be placed away from any EMF source and should be tested with the gauss meter to identify a zero reading. (Tank should not be placed near any electrical device or active outlet)

Data Collection

Spectrophotometer

1. Plug in the spectrophotometer, twist left front knob

2. Pour Acetone and ethanol mixture (80% acetone, 20% ethanol) into a 250mL Erlenmeyer flask

3. Pour approximately 7mL of the mixture into four culture dishes

4. Remove approximately 4 grams from each sample

5. Place each sample into different culture dishes

6. After thirty seconds, place one sample at a time into a tissue grinder; grind

7. Use a pipette to extract the mixture of, now, chlorophyll, acetone, and ethanol

8. Place each extract into individual centrifuge tubes

9. Set the centrifuge to stop in 5 minutes and put on protective face mask; make sure area is either evacuated or surrounding individuals also wear protective gear

10. Once the centrifuge comes to a complete stop, open and take out the centrifuge test tubes and test tube holders

11. Using the pipette, extract the chlorophyll samples from the centrifuge tubes and pour into individual spectrophotometer cuvettes

12. Pour an equal amount of acetone and ethanol as the amount of chlorophyll extract into another spectrophotometer cuvette (this will be the “blank”)

13. On the spectrophotometer, using the right front knob, set the desired wavelength

14. Using the left front knob, calibrate the spectrophotometer to 0.0 (be sure the machine is set to ‘transmittance,’ if not, press ‘mode’ until it reads so)

15. Place the blank into the sample compartment

16. Using the ‘mode button, set the system to ‘absorbance’

17. Using the right front dial labeled ‘100% TOA,’ very carefully turn the knob so ‘Data’ reads .100

18. Remove the blank and place the each of the experimental mixtures inside the sample compartment

19. Close the top and read the number under ‘Data;’ record

20. Repeat procedure for multiple trials

Analyzing Data

1. Type data into a graphing program

2. Find the average of all trials for both the control and experimental group (making one complete set of data for each)

3. Graph both averages on a line graph to compare the amount of change the EMF had to the percent of light absorption over varying wavelengths