@ayo You don't need to allow 500 characters: 128 is enough, or 256 at most. Even if those are just zeros and ones, it's as large space as a typical key for symmetric encryption (#AES).
Just make sure you aren't restricting the language in a stupid way like the "at least one" bullshit.
OTOH, setting up a minimum length of say 12 characters does make sense.
Welcome to your niu world ! We are a cute and loving international community Ｏ(≧▽≦)Ｏ !