SUPPLIES:

• Floating Thermometer: These can be purchased at your local aquarium store where they typically run about $3.00 a piece. You can also order floating thermometers through science catalogs.
• Aquarium Tank(s): Students often have aquarium tanks at home that are not being used. This is an ideal source for tanks. You also might even get lucky at a local garage sale and/or flea market. Aquarium stores often have sales on smaller tanks and might even give you a better deal if you explain to them the purpose of your purchase.
• Gravel: The gravel that you use in the tanks should be specifically made for aquariums. This can be acquired at a local aquarium store or through science catalogs. Once again, students are an excellent resource for these types of materials, so don't forget to ask.
• Tap Water: Remember that the procedure for this investigation calls for tap water, not distilled or purified. You may uses these other sources if you choose, but they will typically cost you money.
• Aquarium Tank Sealant: Tank sealant can be purchased at your local aquarium store. Most tank sealants work well if the directions which accompany them are followed correctly. Be sure to read these directions before the sealant is needed so you will know how much time to allow the repaired tanks to cure before you fill them with water. This may become very important if you are pressed for time during the project.

SPECIMENS:

• Algal inoculum from local pond: You may want to collect pond water or have students collect it and bring samples into class. Remember to tell students to label where and when they collected each sample. If a variety of samples are available you may want to have students look at each sample under a microscope and then give them the choice as to which inoculum they wish to put in they tank. Students who are allowed to choose their sample inoculum should also be required to explain why they choose a particular sample.
• Elodea / Anacharis (recommended 5 bundles/10 gallon tank): These fresh water plants can be acquired at your local aquarium store. Aquarium stores often receive shipments of live materials once a week. You may want to call in advance to ensure the store will have enough in stock for your needs.
• Large snails (recommended 2/10 gallon tank): Your local aquarium store will have snails available for purchase. You will find they vary in size and cost (some snail varieties can run as much as $3.00 to $5.00 a piece). It would probably be in your best interest to call the store in advance and let them know what your needs are to ensure they have the most desirable materials in stock.
• Guppies and/or Feeder Goldfish (10/10 gallon tank): Once again, let your local aquarium store know your needs well in advance to ensure the correct materials are in stock.

TESTS:

• Hydrometer: Hydrometers can be made by following the directions found in the teacher guides. You can also purchase a hydrometer from an aquarium store or science supply catalogue.
• Temperature: During this project students will be recording both the air and water temperature in their tank. You will need an easily accessible air thermometer in your classroom, as well as floating thermometers. It is recommended that if floating thermometers are used they are not left in the tanks. This is due to the fact that you may find them an easy target for theft if your tanks are not covered securely. If the floating thermometers are removed from the tank after each measurement, make sure to remind students that after they put the thermometer into their tank they must wait before taking a reading to allow time for the thermometer to adjust to the water temperature.
• Water Quality Test Kits: The SnapTest or Chemets Kit is a simplified test method which uses an ampule (vial) that your students place in a beaker of water and snap off the tip. The ampule fills with water and it changes color. The color is compared to a set of ampules (provided with the kit) for the immediate reading of results. These test kits are simple and can result in more accurate measurements because they do not involve the mixing of chemicals. Below you will find more information on how to order the water quality test kits for dissolved oxygen, nitrates, and phosphates.
• Use the following links to order Snap Kits:
  • http://www.wardsci.com/ WARD'S Biology is a science supply catalogue where you can purchase the Instant Water Quality Testing Snap Kits. Order numbers for the Snap Kits in the 2000 catalogue (page 714) are as follows: Dissolved Oxygen (Range: 0-12 ppm): kit - 21 W 9073, refill - 21 W 9057; Nitrate (Range: 1-5 ppm): kit - 21 W 9076 refill - 21 W 9060; Phosphate (Range: 1-10 ppm): kit - 21 W 9078, refill - 21 W 9062, activator solution refill - 21 W 9089. Phone number: 1-800-872-7289.
  • http://www.chemetrics.com/: CHEMetrics, Inc. is an online science supply company which specializes in selling water analysis test kits. Phone number: 1-800-356-3072.