I swim. Not usually in pools though. I typically swum out of necessity. I’ve had to pull a flooded kayak, through fast currents many times.
I’ve definitely been bumped into, by fish before. In the ocean, I’ve been hit by some pretty big fish. I couldn’t see what they were. Pretty sure I was hit by a shark once. It was big, and had like sandpaper skin. It left a big scrape on my leg, that looked like road rash.
I of course get the tiny fish, that bite your leg hair. When I kayak the Edisto, I usually dangle my legs over the side, and thousands of the tiny fish nip my legs.
Once, I was snorkeling on a reef , about a mile off of Key west. I rented a ride, on a big boat, that took about 75 people out with us. They sold these things that looked like candy bars. The idea, was to attract more fish towards you. BIG mistake. As soon as the fish realized I had it, they all attacked me. I had to hold it out of the water, because they were biting me everywhere. I eventually just threw the bar a good 20 ft away.
I get nipped by crabs all the time. Bastards can hurt. We have lots of blue crabs in our local brackish rivers. Whenever I step out of my canoe, they go after my toes.
I’m not a fan of swimming…