Wed. Dec 12, 2018

Geoduck Broodstock Experiment

Water chemistry

  • Steven calibrated all Apex pH probes

  • Titrator pH calibrations were inaccurate again. After 3 attempts decided to poison samples and not run the titrator. pH calibration data here.

Attempt 1 @10am:
| standard | mV | pH |
|———-|——–|——|
| 4.0 | 164.3 | 4.12 |
| 7.0 | 12 | 6.79 |
| 10.0 | -154.2 | 9.7 |

Attempt 2 @2pm:
| standard | mV | pH |
|———-|——–|——|
| 4.0 | 167.1 | 4.08 |
| 7.0 | 8.4 | 6.85 |
| 10.0 | -159.6 | 9.79 |

Attempt 3 @3pm:
| standard | mV | pH |
|———-|——–|——|
| 4.0 | 167.5 | 4.07 |
| 7.0 | 6.5 | 6.89 |
| 10.0 | -159.0 | 9.78 |

***need to order new pH probe

  • Kaitlyn took discrete measurements and 125mL water samples from all 6 tanks starting at 4:40pm. Added 50uL mercuric chloride to all bottles, and stored in box below titrator.

  • I downloaded Apex data

Respirometry:

  • Set-up (took 3 hours and started setting up at 11am)
    1. Finish preparing 7 new chamber lids
      • cut and add clear hose to lids for filling chambers (just cut the existing hose on Sam’s 4 lids in half)
      • flex tape the corner cracks near the pump cord in Sam’s 4 lids because the silicon doesn’t make a good seal
      • number Sam’s 4 pump plugs with paint pen
      • have 11 total chambers
    2. Rig up outlets for powering all the pumps
    3. Make 2 additional platforms for chambers to stand on while in water bath (tanks)
    4. Move geoducks to make space for platforms and chambers
    5. Add treatment water to all chambers
    6. Match up O2 and temp. sensors to chamber numbers and fix in cable glands on chamber lids
    7. Power up pumps and make sure they run
    8. Determine biovolume of randomly selected animals and PVC stand to go in chambers
      • Biovolume data
        • This would benefit from a more accurate volume measuring method (e.g. a 5L beaker or a 10L beaker. We are currently using the chamber itself to estimate biovolume of these large animals and the resolution is poor.
    9. Top off chambers by pumping treatment water in through clear hose and cap hoses
    10. Tighten all cable glands
  • Started trial by ~2pm, and stopped at 3:30pm

***need to measure total chamber volume in order to normalize animals

  • Clean-up (~1 hour)
    1. replace animals to their original tanks
    2. remove probes from lids and soak in fresh water (used one chamber for this)
    3. hose off platforms, chambers, and chamber lids
    4. rinse pumps with fresh water
    5. wipe probes dry with paper towel, then wipe with 70% ethanol. Coil up and place in original plastic bags
    6. export data from PreSens software
Written on December 12, 2018