Jan Rabie Tidal Pool. A tidal pool is a natural bath of seawater protected from the surf by surrounding rocks; it is cleaned twice a day by the action of tide flowing and ebbing. The floor is uneven - sometimes deep enough that you cannot stand with head above water, most times knee deep to chest deep.Kelp is a type of seaweed with long strong stem supporting a head of smooth brown leaves that float in the seawater. Often the kelp is floating free, drifting slowly with the current. You will find kelp in the tidal pools and on the beaches. It is in no way dangerous. If you are a swimmer who takes pleasure in the invigorating glow of emerging from water in the range 12 degrees C to 16 degrees C, take a dip here