Right, yes. It's a very interesting question and I think it depends on the species you're working with.
For example, species of Arctic char actually grow best at really high densities of up to 200 kilograms per cubic metre, which is absolutely incredible. That's 200 kilograms per 1,000 litres. That's one part in five fish, and they actually get stressed at lower densities. So I think it depends a lot on the species. Salmon are schooling animals. They're used to fairly high densities. We don't know enough about density effects on social hierarchies and things like that. That's an area of current interest and something that will probably be investigated in the not too distant future.