The goal of the project was a collaboration to increase sustainability in the food industry by converting low-value brewing industry byproducts into high-value feed additives for use in aquaculture. Brewer's spent yeast was processed enzymatically and brewer's spent grain was used to cultivate black soldier fly larvae. The products were then top-coated onto a commercial feed. The overarching goal was to explore the effects of the feed additives on the production, health, and intestinal bacterial community of the rainbow trout. Inadvertently, the effect of thermal stress on the intestinal bacterial community of the rainbow trout was explored as well.