Huddling

updated most recently August 18

On August 5th, PW did a spawn and set aside a cohort in a 300 liter conical to get into the hudls. Ariana and I went out on the 9th to move them. We set up 6 units in the left tub and 4 units in right tub, with an additional blank unit in the right tub.

Check out her post here

It was estimated we started with 2 M larvae, placing about 200k in each unit.

The general parameters included having the header pumping at 2 min on / 2 min off at ~30 rpms. The target flourescence at unit level was 15-20. To obtain this the header flourescent was set such that the dilution of a half plastic cup in a tri-pour reads out at 50. At the time, this equated to about 4 liters of Pav / day in header, topped off with seawater (in 50 gallon trash can).

right-tub

AUG11

Larvae feed header has been replenished everyday, often also adding .2 g EDTA to heated water header. Filters needed rinsing about every 2-3 days. The left tub (6 units) were dropped / filtered for the first time on August 15 (6 days in hudls and 10 days since spawn). All 6 units were run through 125, 105, 80, 60.

Each screen was washed into 500ml counting came out at the following within 40ul.

60 um - few dead shells 80 um - 7 larvae 105 um - 4 larvae 125 um - 8 larvae

Lets math that up… 500mls = 500,000ul 500,000 / 40 = 12500 * 3 = 237,500

6.3* 237500 = 1.4 million larvae in system.

These were combined and placed back into clean units in left tub. All units moved up to 75 um filters. Right tub was not filtered. Wanting to see how long might be able to go with out dropping.

Pics from August 15:

larvae

system

Matt will likely check on food on August 16, plan is to go out August 17.


Aug 17
It appears no food was added August 16 (which is fine as I said not necessary as would last) it did. However Flour readings in units was only about 7. I cleaned out algae header, refilled and set set system to go at 25 rpms

August 18 AM Went out and feed pump seemed to shut off soon after I left on 17. Flour readings about 7. I juiced them up at about 75rpms for 20 minutes, then set back at 30 rpms. Readings about 40 when I left.

Written on August 18, 2023