Cleaner Fish is an umbrella term for several different species that pick lice off farmed salmon and farmed rainbow trout.
Cleaner fish producers sold 2,049,000 pieces of cleaner fish for stocking in salmon cages in 2013.
The corresponding figure for 2012 was 703,000 pieces. In addition to farmed cleaner fish, salmon farmers also used wild cleaner fish. Overall, roughly 15,381,000 cleaner fish were used in cages in 2013.