Should seacocks be open or closed whilst open water sailing?

Seacocks should generally be closed while sailing in open water to prevent any accidental flooding in the event of a hull breach or other emergency. Keeping them closed also minimizes the risk of debris entering through the openings. However, it's important to ensure that all necessary systems, such as bilge pumps and water intake for cooling, are functioning properly before setting out. Always follow your vessel's operating procedures and guidelines for safety.