I'm in the top 1% with 102 clown fish eaten.
Find the clown fish in nooks, crannies, and caves.
My high score was with the Mosasaurus, Level 7 equiped with the Clown Baby and the Oceana Baby, the Oceana emblem, shark vortex, laser and skateboard. The skateboard is probably not really necessary as there aren't any clown fish on the land but it makes it easier to zip back and forth.
My two next highest scores were with Big Daddy, equipped with the baby Big Daddy, the Clown Baby, laser, shark vortex, Oceana emblem, skateboard and jet pack - I got to 87 with him.
I think I could have scored even higher if I had the Mosasaurus baby to help eat. Oh, and I bought the shark signal to have an extra baby slot on Mosasaurus.