This forum requires a 10-character password. I have registered for hundreds, maybe thousands of things over the past 20 years, and never encountered such a requirement.
This forum is hardly a high-value item. Having such a requirement is a bit like carrying a huge, expensive, heavy bicycle lock for an antique rusty bicycle that nobody would want to steal anyway.
This is an example of where high password requirements can lead to less security, because people have to pick unusual passwords that they then have to write down.
Take it from The Man (Bruce Schneier) who wrote The Book (Applied Cryptography) on security: “To determine how much security you need, you must ask yourself some questions. How much is your data worth? How long does it need to be secure? What are your adversaries’ resources?” [p. 166]
It’s hard to believe that anyone has a burning desire to hack into your forum, particularly since they can become a member for free. Any user who is concerned that your password file will be stolen, can make his password as big as he likes. For us trusting souls, we should be able to make it as small as we like.