Types of fishing in the UK

Guys,

I am currently in the process of writing and launching a UK based site
that will, among other things, help people find new friends to persue
their hobbies. Fishing is one activity that we are concentrating
strongly on. I, however, have not fished in a while, and so was
wondering if you guys could spare 2 minutes to help me.

Currently a user will have to enter the type of water they fish in
(sea/fresh), but I would also like to allow a user to enter the fish
they go after as well, so as to enable more focussed searching. What
fish do people fish in this country (I know that carp is very popular,
but that's it).

Many many thanks,

Si