The pots are called pitchers
in fact, pitchers die faster when fed more. Also, feeding animals tend to cause rot inside the pitcher and make them die off faster. Insects are more easily digested and more of it's nutrients are used by the plants. As for fish, since you grow it so well, I can't say it's bad for the plant, but I can't imagine the plant using all the nutrients from the fish such as calcium, iron and carbohydrates. Therefore, bacteria thrive more easily on these dead fish, causing more rot and pitchers to dry off.
Feeding one BIG stuff also causes rot faster. I once fed half a slug into my truncata. The pitcher liquid was completely murky and blur within a day and in a week, the pitcher dried off.