tudents hatch brine shrimp (Artemia) from eggs and track hatching success and growth over several days using simple equipment. A control culture is compared with single-variable changes to explore what helps or harms development.

1. Gather gear: clean jar or bottle hatchery, marine/sea salt, dechlorinated water, brine shrimp eggs, optional air pump with air stone, light source, thermometer, fine net or sieve, labels.
2. Make brine: dissolve 25–35 g marine salt per liter of dechlorinated water (aim for typical seawater salinity).
3. Set up hatch: fill container with brine, add gentle aeration, sprinkle a small pinch of eggs on the surface, and place near a light and warmth (about 24–27°C).
4. Observe hatch: check at 24–48 hours for orange, swimming nauplii; record time to first hatch and estimate numbers.
5. Rinse and transfer: collect nauplii with a sieve, rinse briefly in clean brine, and move to a clean container of brine for rearing.
6. Feed lightly: once yolk reserves are used (day 1–2), add a tiny amount of yeast or microalgae suspension; avoid clouding the water.
7. Track data: each day note temperature, salinity, behavior, and an estimated size stage or count; keep the control conditions unchanged.

Lesson: Brine Shrimp in the Classroom - saltlakebrineshrimp:

📄 Classroom Science Experiment - Brine Shrimp: https://brineshrimp.com.au/classroom-science-experiment/

• Temperature: run parallel cups at cool (~18–20°C), room (~22–24°C), and warm (~26–28°C) to compare hatch rate and time.
• Salinity: test lower (15–20 g/L), normal (25–35 g/L), and higher (40–50 g/L) salt to see effects on hatching and survival.
• Light intensity/duration: compare continuous light vs normal classroom light vs dim conditions; keep temperature constant.
• pH (mild range only): compare pH ~7.5, ~8.0, ~8.5 using aquarium buffer; avoid strong acids or bases.
• Aeration: gentle bubbling vs no aeration to test oxygen/mixing needs.
• Stocking density: few eggs vs many eggs to see crowding effects.
• Food type/amount: yeast tint vs commercial microalgae; light vs heavier feeding.
• Fair test note: change only one factor at a time and include replicates.

• Use only aquarium sea salt and dechlorinated water; do not ingest materials; wash hands after handling.
• If using a heater or air pump, keep cords and plugs dry and secured; teacher handles electrical setup.
• Adjust pH only with aquarium buffers; avoid strong household chemicals.
• Rinse spills and salt residues from benches; keep solutions away from eyes.
• Dispose of excess salty water down the sink with plenty of fresh water; never release organisms into local waterways.

• Which condition produced the fastest hatch and why? (Warmer temperatures within the safe range speed metabolism and development.)
• How did salinity change hatching success? (Outside the optimal range, water balance stresses embryos and reduces hatch.)
• Why does gentle aeration help? (It supplies oxygen and keeps eggs in suspension, improving uniform conditions.)
• What evidence shows overfeeding? (Cloudy water and fouling, followed by stress or mortality.)
• How does changing only one variable strengthen your conclusion? (It lets you attribute differences to that factor rather than hidden changes.)