======Brine Shrimp Hatching and Growth======


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**Alternative titles:** Sea Monkey Hatch and Raise
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====Summary====                   
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====Procedure====  
  - 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.
  - Make brine: dissolve 25–35 g marine salt per liter of dechlorinated water (aim for typical seawater salinity).
  - 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).
  - Observe hatch: check at 24–48 hours for orange, swimming nauplii; record time to first hatch and estimate numbers.
  - Rinse and transfer: collect nauplii with a sieve, rinse briefly in clean brine, and move to a clean container of brine for rearing.
  - Feed lightly: once yolk reserves are used (day 1–2), add a tiny amount of yeast or microalgae suspension; avoid clouding the water.
  - Track data: each day note temperature, salinity, behavior, and an estimated size stage or count; keep the control conditions unchanged.



====Links==== 
Lesson: Brine Shrimp in the Classroom - saltlakebrineshrimp: 
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📄 Classroom Science Experiment - Brine Shrimp: [[https://brineshrimp.com.au/classroom-science-experiment/]]\\


====Variations====
  * 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.



====Safety Precautions====
  * 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.




====Questions to Consider====
  * 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.)