Yes, it is still there. Out in the open ocean a tsunami is almost unnoticeable. The amplitude (height) of the wave is many times lower, and it has a much longer wavelength. If you were on a boat in the middle of the Pacific, the slow rise and fall of the water level will not be noticed by anyone onboard. Also, each individual water particle doesn’t move far when a wave passes through it, with the molecules following a circular pattern. There is only large horizontal movement of water in shallow areas. The plastic atlantis will hardly budge when a tsunami goes through it.