Weekend Update with L. Spencer

Ups and downs this weekend!

Friday, 10:00am: asked PSRF to, in preparation for them lowering the heated line to 14degC, close the ambient line and turn off the mixing valve. I was alerted that they weren’t reducing T until Monday, so I thus directed them to instead, simply increase the mixing valve set point to 16degC (to maintain 18degC in culture tanks over the weekend). They kindly obliged, however an error was made with re-opening the ambient line (likely due to a broken valve handle, which makes it difficult to know whether the line is open, closed, or somewhere in-between).

Saturday, 5/13 I checked the temperatures online @ ~1:00pm, and (oh no!) the header tank read 25degC. I hopped on the ferry ASAP and, at 2:30pm discovered that indeed, the mixing valve had closed all inflowing water & header tank was drained. I set the mixing valve to “manual” and opened it. Observed that the algae, which had been reliably dosing, mostly flowed into the 2 closest broodstock buckets on the bottom shelf - SN-6 low pH & NF-6 low pH - the buckets were very green, so I dumped and rinsed them. I also unplugged the immersion heater for the remainder of the weekend.

I quickly scanned the catchment buckets for larvae: found a few in HL-6 low pH. I screened them on 100uM (using 200uM ontop to remove debris); and counted. They weren’t very active, likely due to spending ~24 hrs without flow / algae. I kept them anyway to practice my rearing system.

HL-6 low pH: Sampled 1.00 mL -> 78, 65, 66 -> 70 larvae/mL average in 50 mL _> 3,500 larvae.

Sunday, 5/14: Spent a full day getting the rest of the larval rearing table ready. Plumbed in an air line (using 1” schedule 40 pvc pipe & flex pipe, 1/8” tapping bit, 1/8” air line valves). I prepped more 5 gallong buckets by drilling the outflow holes and installing [?]. I have several banjos that need to be re-tapped as the holes are too small for the threaded/barbed adapter. I found that the 1/8” tapping bit that I purchased for the air line also works for the banjos.

Collected larvae! 4 more populations have spawned. I sampled only for count purposes, and preserved on a well plate to count on Monday. Here are all the counts to date:


No larvae found in the following populations:

  • NS-6 low pH B
  • NF-6 amb pH A
  • NF-6 amb pH B
  • NF-10 amb pH A
  • SN-10 amb pH A
  • SN-10 low pH B
  • NF-10 amb pH B
  • NF-10 low pH A
  • NF-10 low pH B
  • SN-6 low pH B
  • NF-6 low pH A
  • SN-6 low pH A
  • HL-10 low pH
  • HL-10 amb pH
  • HL-6 amb pH
  • K-6 low pH
  • K-6 amb pH
Written on May 14, 2017