Using cleanerfish for sea lice biocontrol is becoming a common practice in salmonid aquaculture in the North Atlantic, however, there is still much to learn. At the University of New Hampshire, research focuses on understanding cleaning behaviors and cleanerfish-salmonid interactions in sea cages. Currently, lumpfish cleaning behaviors are being assessed with steelhead trout, a salmonid important to the future of New Hampshire’s finfish aquaculture industry and one that hasn’t been previously evaluated with cleanerfish. Lumpfish-trout interactions are recorded through a combination of underwater video, diver observations, and through monitoring the movements of fish implanted with transmitters (Vemco V7P tags) yielding 3-dimensional positions. Along with the collection of behavioral observations and movement tracking, sea lice infestations are monitored through routine sampling to determine the effectiveness of lumpfish treatments. This novel study goes beyond just mapping lumpfish movements, but provides greater insight into how the two species interact with each other which will illuminate best practices for utilizing cleanerfish in salmonid aquaculture.