Spatial and temporal changes in epibenthic communities at deep, hard bottom aquaculture sites in Newfoundland

•We studied the epibenthic response to aquaculture at deep (>30m) hard-bottom sites.•Visual indicators (bacterial mats and opportunistic polychaetes) appeared rapidly.•Intermediate successional stages of enrichment were elusive.•A combination of visual indicators is useful for assessing aquaculture impacts.