My daughter volunteers at the PK fish hatchery and last evening they spawned Stipers and Hybrids.
I was up there fishing so I went and watched the initial process. They have to wait on the fish till its time and it started at 7 and finished up just after midnight. In 48 hours there should be new swimmers.
Once they spawn the Stripers will be sent to the San Marcos hatchery to be grown to 1 1/2” when they will be stocked in Texas lakes.

In the first hour the eggs that did not get fertilized turn white and rise up in the containers. Some will run out and be filtered out. They also start vacuuming the unfertiled eggs so the water does not degrade.
There will be someone there 24 hours a day constantly monitoring the water flow so that the eggs constantly get fresh water. Too much water and the eggs start rising and could be lost so someone is adjusting water flow as needed.

This is a few females in 5 tanks waiting to be used. The fisheries manager inspects them to see if they are ready to spawn. I was told they have a one hour window so its wait until the fish are ready.

Each of the females used are tagged with a colored ribbon, held in 5 tanks during the process. When they spawn each fish’s eggs are sized and counted. They measure the volume of the container to estimate the number while a tech takes a sample to measure the size of the eggs under a microscope. He will later count the eggs in a small sample of each fish.

This is Mike. He is vacuuming the white unfertilized eggs. The tube is held a couple inches above the dead eggs and they are sucked out so they do not contaminate the water. Any biomass can degrade the water. The water used is well water and its kept at a certain temp and several factors like ph and do are constantly being watched.

This is 1/4 of the containers.
Water is sent down a tube to the bottom of the container and moves up through the eggs. Initially the overflow runs out and the water is disposed of until the milt is gone, then the overflow is reused. The overflow is screened to catch any biomass that can degrade the water. Most of it is the white unfertilized eggs.

Thank you Texas A&M .

While I was there 8 or 9 people were there. It took that many people to do the work and document it all.

Went through there several times when I was with the BRA. It's an impressive operation.

Very interesting, thank you for sharing...