Let's take a look at what the design for these features would look like.
Our profiles will collect basic data about a user. Some items that we will collect are:
Various IM (Instant Messaging) IDs
The users' post/comments
Some basic fish related information such as how many fish tanks they have and how many fishes they have
In addition to this we will allow our profiles to have dynamic attributes. While these could be dynamic from a user's point of view, we will currently restrict this feature to allow only an administrator of the site to add additional attributes. Some examples of dynamic attributes are "about you", "occupation", and "your (reef/aquarium) setup".
The image will look like this:
This structure basically allows a profile to have as many extended attributes as the site administrator wants to collect data for.