Underwater ship renovation from a professional: osmosis protection - corrosion protection

The underwater hull... for many boat owners it can only be worked on very laboriously and usually with moderate success. But a well-maintained underwater hull is the guarantor for the value retention of a yacht.
Rust on the keel, leaking rubber joint in the keel-hull connection, damp rudder blade, over-coating, osmosis?
What is osmosis, how can it be detected, how can it be prevented or remedied? Is there a professional answer to rust and corrosion in steel and aluminum?
These are the questions we will address in our lecture and, with the help of clear photographic material, we will provide an entertaining and to the point insight into the professional underwater ship refit with the technical possibilities of the specialist.