I teach aquatic exercise from senior fitness to elite athlete, from post rehab to performance enhancement. Some of the best shoe companies I have found for this are:
These are usually quality shoes that hold up for a long time. The pool bottom is important as well. Most of these shoes do very well on a rough/textured bottom, which is the type of pool bottom that I prefer. I have not had to deal with a smooth/slippery pool surface in years. But almost any shoe is better than no shoe in a shallow water situation. As I teach the class, I go for a high quality long lasting shoe. But I have worn simple slip on water shoes when I couldn’t find a decent replacement shoe in a pinch. They don’t hold up well though.