Trying to keep clean ballast and doing a minimal exchange of seawater was always a challenge when I sailed as chief mate on a 900 x 129 foot containership. We sailed from some of the dirtiest port waters in Asia.
We often left port with very little leeway as far as stability the way they loaded us. (Ship's crew has little or no say any more on what goes where)
After many hours loading in port and then inspecting container lashings, doing the paper work, departing the port, I had to get the ballast exchanged before we hit rough weather or had burned off too much fuel to still be stable for the operation.
Saw one picture where a Chinese tanker broke in half alongside the dock.
When the chief mate screws up it usually makes the news.
Best regards to a Capesize sailor.