Lesson 5: Defining the Problem: Researching System Corrections

What exactly is the problem in our system?
Is the issue biological, chemical, mechanical, or a combination?
What organisms or mechanisms could reduce imbalance?
How do we evaluate whether a proposed solution fits our specific system?
What trade offs might accompany each intervention?

Intervention
Bioload
Filtration
Plant biomass
Surface area
Mechanical filtration
Biological filtration
Compatibility
Carrying capacity
Trade off

HS ETS1 2
Design a solution to a complex real world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.

HS LS2 1
Use mathematical and computational representations to support explanations of factors that affect carrying capacity of ecosystems.

Science and Engineering Practice, Engaging in Argument from Evidence
Science and Engineering Practice, Constructing Explanations
Science and Engineering Practice, Analyzing and Interpreting Data

Crosscutting Concept, Systems and System Models
Crosscutting Concept, Cause and Effect
Crosscutting Concept, Stability and Change

Students evaluate solution options.
Students justify claims using evidence.
Students weigh strengths and weaknesses of alternatives.
Students determine feasibility in a constrained scenario.

Day 1: Defining the Problem Clearly

Students review post fish data and documented changes:

Ammonia levels
Plant response
Algae presence
Water clarity
Fish behavior

Students must write a precise problem statement:

The system is experiencing ______ due to ______ as evidenced by ______.

This forces clarity before jumping to solutions.

Students then categorize potential solution types:

Increase plant biomass
Add biological filtration surface area
Introduce algae consuming organisms
Adjust feeding practices
Modify light exposure
Improve aeration

The goal is to expand possibility space before choosing.

Day 2: Research and Proposal

Students research potential interventions such as:

Adding fast growing nutrient absorbing plants
Increasing surface area for bacteria colonization
Adding compatible algae consuming organisms
Installing additional filtration media
Reducing nutrient input

Students evaluate each option using a structured checklist:

Does this address the root cause?
Is it compatible with current fish?
Does it increase system stability long term?
What new risks could it introduce?

Students submit a brief intervention proposal including:

Identified problem
Proposed solution
Justification using system data
Anticipated benefits
Possible unintended consequences

This is not implemented yet. It becomes the launch point for Phase 2.

DOK Level

DOK 2 for identifying appropriate solution categories.
DOK 3 for justifying intervention using evidence and trade off reasoning.

Aquaponics and aquaculture managers must diagnose system imbalances and select interventions that match specific system constraints. Adding organisms without compatibility research or increasing filtration without understanding bioload can destabilize operations. Students are engaging in authentic environmental problem solving.

More organisms always solve imbalance.
Algae eaters eliminate the root cause.
Mechanical filtration replaces biological filtration.
A quick fix guarantees long term stability.
One solution addresses all system issues.

https://docs.google.com/document/d/1siFIsOAs45CxuUlyJt9dNRdT70eTva14fJMeE1qXHPk/edit?usp=sharing%20

Problem Statement Submission

Students submit a written problem definition supported by parameter data.

Intervention Proposal

Students submit a concise proposal identifying one intervention with justification and acknowledgment of potential trade offs.

These serve as process checkpoints and transition artifacts into Phase 2.