Another useful fish goo application is what I used to do back in the day, which was on my final transplant into 3 gallon pails that the plants would finish in, I would mix about 2 tablespoons of undiluted fish emulsion really well into the soil. This avoided the yellowing at the end of the plant's life, and as the roots grew into the new soil, they would access the added Nitrogen and Calcium the fish goo provides.
But yeah, I had thrips. Boo, thrips.