It is clear fish can remember long enough to learn things, like where the food comes from--why else would they come to the top of the tank when you approach?
the story is, it last 3 seconds. This is debatable because it seems as though fish can remember certain things, like when they are fed. I think its still being figured out how longn their memory actually is
The memory of the fish is 2 seconds to 12 seconds or depending up on what type it is like the golden fish has memory span for three months,it is depend on the type.