1. Creating Your Balanced Ecosystem

2. Standards Covering
SC.7.L.17.3 Describe and investigate various limiting factors in the local ecosystem and their impact on native populations, including food, shelter, water, space, disease, parasitism, predation, and nesting sites. 
SC.7.L.15.2 Explore the scientific theory of evolution by recognizing and explaining ways in which genetic variation and environmental factors contribute to evolution by natural selection and diversity of organisms. 
SC.8.N.1.6: Understand that scientific investigations involve the collections of relevant empirical evidence, the use of logical reasoning, and the application of imagination in devising hypotheses, predictions, explanations, and models to make sense of the collected evidence.

3. Objectives
After being assigned an organism per the Aquaponics System Animal Selection Guide, students will research general physical characteristics and/or behaviors of animals, and assess their use for creating a balanced aquaponics ecosystem, with 70% accuracy. Given the Balanced Ecosystem Probe Revisited, students will label a balanced aquaponics system diagram, and provide a research-based rationale for their selection of organisms in the system, with 70% accuracy.

4. Balanced Ecosystem
An ecosystem is balanced when the biotic (living) and abiotic (non- living) parts of the ecosystem are in equilibrium. This means that the nutrients are able to cycle efficiently, and no community of organisms or natural phenomena is interrupting the flow of energy and nutrients to other parts of the ecosystem.

5. Balanced Ecosystem Probe
On your copy of the worksheet, imagine a balanced ecosystem, and complete the probe by responding to the questions,
What do you need to have in a balanced ecosystem?
What types of animals and plants would you need?
What is the function of each animal and plant in the ecosystem?

6. Stock The Tank
Independently, predict what you will need to go in the tank to create a balanced ecosystem
With your group, compare your predictions with each other

7. Aquaponics system Animal Selection Guide
Complete your Organism Research Data Sheet, then create a poster to document and share research-based findings about your organism. Remember, scientists use empirical evidence to understand and support claims regarding the natural world, therefore, they must use findings to support a rationale for their suggestions.

8. Time to Share!
Students will present their posters, and explain organisms they feel should be included in the system, as supported by their researched findings. Think critically by analyzing the function of each of the animals.
Discussion questions:
Does it play a role in the ecosystem?
Does it disrupt the ecosystem?
Is it economical to include it?
Is it necessary?
Additional questions to elicit student thinking may include:
What animals do you think should go in the tank?
Why did you pick the animals that you did?
How many of each species are you picking?
Are there any fish on the Aquaponics System Animal Selection Guide that should NOT be added to the tank?

9. Recap
There are many ways to create a balanced aquatic ecosystem by including algae eaters, bottom feeders, and swimmer fish.
A balanced ecosystem has living components like animals and plants, and non-living components like water and the clay medium.
Fish tanks need to start with a school of swimmer fish that may include guppies, small tetras, and/or platy, etc. These fish produce waste.
Algae may form in the tank. Plecos clean algae.
Schools of fish should be complemented by the addition of snails or plecos, which will eat the algae and solid waste from the bottom of the tank, keeping it clean.
Despite not fitting in the current tank size, lizards, frogs, and turtles are recommended for larger, more established aquaponics ecosystems.

10. Just Grow Student Response Template
Complete this and justify your selections using research-based findings.

11. Balanced Ecosystem Probe Revisited
Document a revised design for a balance aquaponics system by completing the Balanced Ecosystem Probe Revisited. This time, however, you must include a short research-based rationale for revisions made.