The biological limitations that I was speaking to were the control systems that we put in and the research systems where we maximize temperature in order to maximize growth. There is a limitation in temperature profiles. Obviously, in open-net pen systems you don't have control over that, so you have a natural temperature control.
The other limitation was in the density issue, and open-net pen systems, again through stress mapping activities and research, have demonstrated that the densities that fish best survive in and best grow in are below the numbers I mentioned, 17 to 22 being the maximum, the optimum being around 10 kilos per cubic metre. That again is a density that we're not pushing the fish beyond. Again, in open-net pen systems that's a very feasible system. So as far as the parameters that I was speaking to, open-net pen systems are very sustainable.