This is because of the salt in the water
The salt added to water makes the water colder so salt water evaporates slower than just plain fresh water.
Salt water needs to be much colder than fresh water to freeze because salt melts ice.
It is easier to float in salt water than in fresh water.
Salt water is more dense than fresh water. So when you're in salt water you float more than when you are in fresh water
Salt water has a greater density than fresh water. So the same object will foat higher in salt water than in fresh, and some things will foat in salt water that are too dense to float in fresh water.
Salt water is denser than fresh.
there is a higher concentrate of salt in salt water than in fresh water
Salt water freezes at a lower temp than fresh, meaning colder. It may freeze faster when chilled enough be cause the salt would disrupt the plateo of the water so it may freeze faster.
Salt water is more buoyant than fresh water is, because salt water is slightly more dense. -- Anything that floats in salt water will float higher than it does in fresh water. -- Anything that sinks in salt water will sink slower than it does in fresh water. -- Anything that just barely floats in salt water may possibly sink in fresh water.
The freezing point of salted water is lower than the freezing point of pure water; this is a phenomenon known as freezing point depression when a solute exist in the solution.
Because salt water is denser. If you pour salt water and fresh water [one with food coloring] into a glass, the salt water will sink below the fresh water. You are only a bit denser than salt water.