Could wrasse help salmon fish farms thrive in Scotland?
18 October 2011 Last updated at 02:50 BST
Anglers and land owners have expressed concern about the impact of farmed fish infected with sea lice on wild fish.
A proposal to use wrasse as cleaner fish to deal with sea lice is being considered by scientists in Machrihanish.
Paul Featherstone, of Marine Harvest, and John Rea, of Scottish Sea Farms, spoke to BBC Scotland's Ken Macdonald.
BBC Scotland Investigates: Scotland's Fishy Secrets will be broadcast on BBC One Scotland at 22:35 on Tuesday 18 October, and then on the programme website.