These little brook trout have come a long way since we started sharing the fish rearing process with you! You've already seen spawning in November, and shocking and picking in December. Here's hatching and "swim up"! As thousands of eggs hatch, the sac-fry wiggle their way down through the slots in the hatching trays into the tank below where they settle on the bottom. They’re called sac-fry at this stage because they still have an attached yolk-sac. They get all the nutrients they need from the