No, but. The pe tubes are not affected directly by immersion in water during swimming, (as long as the procedure recovery period s passed and the tubes have seated well).However, all the e.Coli & other germs that exist in the water will have easy access to the sensitive membranes of the middle ear. Most ent's suggest ear plugs if you plan to swim. The consequences of going without vary.
NO but don't do it. They will not fall out if you swim in the ocean, lake, or stream. But you want to make sure you don't get water in the tube which may cause an ear infection. If you will be in the ocean/poo/lake, etc. Wear ear plugs if you or your child has had tubes placed.