Green Crab Experiment Part 7

Treatment Days 5 through 7

Day 5

  • Fixed T6 temperature
    • Added tank to the right side of T6 to insulate it from the 15ºC line. Checked after 15 minutes and temperature increased from 21.6ºC to 22.3ºC
      • 30 min: 22.3ºC to 22.9ºC
      • 30 more min: no increase
    • Probes for front heaters swapped between T3 and T6!
      • T3 heater tried heating T6, but the temperature in T3 did not increase because the back heater was modulating temperature
      • Put proper probe in proper tank and labelled probes, heaters, and controllers with tank numbers
      • Back heaters in correct tanks, so just a front heater tissue
    • Confirmed T6 reached the proper temperature
  • Checked ammonia. Added 1/2 tsp conditioner when ammonia > 1.0
    • T1: 1.0
    • T2: 0.25
    • T3: 8.0
    • T4: 4.0
    • T5: 0.25
    • T6: 1.0
  • Clean tanks and performed water change for all
  • No mortality in any tanks
  • Feed crabs
    • Debris in T2, T3, and T5
    • T1 and T4: 1/4 tsp
    • T2 and T5: 1/4 tsp
    • T3 and T6: 3/8-ish tsp
  • Airstone disconnected in T6, reattached

Day 6

  • Checked ammonia. Added 1/2 tsp conditioner when ammonia ≥ 1.0
    • T1: 1.0
    • T2: 0.25
    • T3: 8.0
    • T4: 4.0
    • T5: 0.25
    • T6: 4.0
  • Clean tanks and performed water change only for T3 and T6
  • No mortality in any tanks
  • Feed crabs
    • Debris in T2, T3, and T5
    • T1 and T4: 1/4 tsp
    • T2 and T5: 1/8 tsp
    • T3 and T6: 1/4 tsp
  • T3 and T6: crabs hanging out on top of tank

Day 7

  • Checked ammonia. Added 1/2 tsp conditioner when ammonia ≥ 1.0
    • T1: 0.25
    • T2: 0
    • T3: 8.0
    • T4: 2.0
    • T5: 0
    • T6: 4.0
  • Clean tanks and performed water change only for T3 and T6. Removed any and all debris to starve crabs prior to respirometry
    • T2 and T5: less debris than before, but food debris still on the bottom of the tank
    • T3 and T6: food debris under heater and air stones
  • No mortality in any tanks
  • T3: 4 crabs on top
  • T6: 2 crabs on top

Going forward

  1. Continue with experiment
  2. Ask why warm tanks have consistently high ammonia
  3. Update protocols
  4. Create mortality spreadsheet
  5. Organize project repository and datasheets
Written on July 11, 2022